MEC / Mayville Engineering Company, Inc. - Документы SEC, Годовой отчет, Доверенное заявление

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2025 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38894 Mayville Engineering Company, Inc.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 5, 2025 Mayville Engineeri

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 5, 2025 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation)

MAYVILLE ENGINEERING COMPANY ANNOUNCES SECOND QUARTER 2025 RESULTS

Exhibit 99 MAYVILLE ENGINEERING COMPANY ANNOUNCES SECOND QUARTER 2025 RESULTS MILWAUKEE, Wis.

MAYVILLE ENGINEERING COMPANY ELECTS TANIA WINGFIELD TO BOARD OF DIRECTORS

Exhibit 99 MAYVILLE ENGINEERING COMPANY ELECTS TANIA WINGFIELD TO BOARD OF DIRECTORS MILWAUKEE, Wis.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 24, 2025 Mayville Engineerin

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 24, 2025 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or Other Jurisdiction of Incorporation) (

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 1, 2025 Mayville Engineering

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 1, 2025 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or Other Jurisdiction of Incorporation) (C

Mayville Engineering Company Completes Acquisition of Accu-Fab, LLC

Exhibit 99 Mayville Engineering Company Completes Acquisition of Accu-Fab, LLC MILWAUKEE, Wis.

First Amendment, dated as of June 26, 2025, to Amended and Restated Credit Agreement, dated as of June 28, 2023, by and among Mayville Engineering Company, Inc., certain subsidiaries of Mayville Engineering Company, as guarantors, the lenders from time-to-time party thereto, and Wells Fargo Bank, National Association, as Administrative Agent for the lenders (including a full conformed copy of the credit agreement, as amended by the first amendment).

FIRST AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT FIRST AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT (this “Agreement”), dated as of June 26, 2025 (and effective as set forth below), among MAYVILLE ENGINEERING COMPANY, INC.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 26, 2025 Mayville Engineerin

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 26, 2025 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or Other Jurisdiction of Incorporation) (

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 11-K FOR ANNUAL REPORTS OF EMPLOYEE STOCK PURCHASE, SAVINGS AND SIMILAR PLANS PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 11-K FOR ANNUAL REPORTS OF EMPLOYEE STOCK PURCHASE, SAVINGS AND SIMILAR PLANS PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2024 OR ☐ TRANSITION REPORT PUR

Purchase Agreement, dated as of May 23, 2025, among Mayville Engineering Company, Inc., Accu-Fab, LLC and Tide Rock YieldCo, LLC*

Exhibit 2 PURCHASE AGREEMENT by and among MAYVILLE ENGINEERING COMPANY, INC., ACCU-FAB, LLC and TIDE ROCK YIELDCO, LLC Dated as of May 23, 2025 TABLE OF CONTENTS ARTICLE 1 PURCHASE AND SALE; THE CLOSING‌1 1.1 Purchase and Sale of the Interests‌1 1.2 Purchase Price‌1 1.3 Tax Withholding‌1 1.4 Closing‌2 1.5 Closing Obligations‌2 1.6 Escrow‌4 ARTICLE 2 PURCHASE PRICE ADJUSTMENT‌4 2.1 Estimated Closin

Entry into a Material Definitive Agreement, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 23, 2025 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or Other Jurisdiction of Incorporation) (C

MAYVILLE ENGINEERING COMPANY ANNOUNCES DEFINITIVE AGREEMENT TO ACQUIRE ACCU-FAB, LLC Acquisition to provide MEC with strategic diversification into high-growth end-markets, including critical power infrastructure, data center and renewable energy Com

Exhibit 99 MAYVILLE ENGINEERING COMPANY ANNOUNCES DEFINITIVE AGREEMENT TO ACQUIRE ACCU-FAB, LLC Acquisition to provide MEC with strategic diversification into high-growth end-markets, including critical power infrastructure, data center and renewable energy Combined platform adds strategically located facilities and enhances value-added capabilities Expected to be immediately accretive to Adjusted EBITDA, Adjusted EBITDA margin and Adjusted Earnings Per Share MEC to host Accu-Fab acquisition conference call and webcast today at 9:00 a.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2025 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38894 Mayville Engineering Company, Inc.

MAYVILLE ENGINEERING COMPANY ANNOUNCES FIRST QUARTER 2025 RESULTS

Exhibit 99 MAYVILLE ENGINEERING COMPANY ANNOUNCES FIRST QUARTER 2025 RESULTS MILWAUKEE, Wis.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 6, 2025 Mayville Engineering

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 6, 2025 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation) (Co

Submission of Matters to a Vote of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 22, 2025 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation)

Form of Severance Agreement between Mayville Engineering Company, Inc. and Craig D. Nichols.

Exhibit 10.1 SEVERANCE AGREEMENT THIS SEVERANCE AGREEMENT, effective as of the day of March, 2025 (this “Agreement”), is by and between MAYVILLE ENGINEERING COMPANY, INC. a Wisconsin corporation (the “Company”), and Craig Nichols (the “Executive”). WITNESSETH: WHEREAS, the Executive has agreed to serve as the Company’s Senior Vice President Operations and Supply Chain. WHEREAS, the Company is, as

MAYVILLE ENGINEERING COMPANY ANNOUNCES APPOINTMENT OF CRAIG NICHOLS AS SENIOR VICE PRESIDENT, OPERATIONS AND SUPPLY CHAIN

Exhibit 99 MAYVILLE ENGINEERING COMPANY ANNOUNCES APPOINTMENT OF CRAIG NICHOLS AS SENIOR VICE PRESIDENT, OPERATIONS AND SUPPLY CHAIN MILWAUKEE, Wis.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. )

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)

Form of Change in Control Employment and Severance Agreement between Mayville Engineering Company, Inc. and Craig D. Nichols.

Exhibit 10.2 CHANGE IN CONTROL EMPLOYMENT AND SEVERANCE AGREEMENT THIS CHANGE IN CONTROL EMPLOYMENT AND SEVERANCE AGREEMENT, effective as of the day of March, 2025 (this “Agreement”), is by and between MAYVILLE ENGINEERING COMPANY, INC., a Wisconsin corporation (the “Company”), and Craig Nichols (the “Executive”). W I T N E S S E T H WHEREAS, the Executive has agreed to serve as the Company’s Seni

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 10, 2025 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or Other Jurisdiction of Incorporation)

Mayville Engineering Company, Inc. Insider Trading Policy

Exhibit 19 MAYVILLE ENGINEERING COMPANY, INC. Insider Trading Policy This policy applies to all employees at every level of the Company and its subsidiaries, including the directors of the Company. Overview Given that the common stock of the Company is traded on the New York Stock Exchange, there are certain important restrictions and limitations imposed on you under the federal securities laws. A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2024 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM TO Commission File Number 001-388

List of Subsidiaries of Mayville Engineering Company, Inc.

Exhibit 21 Subsidiaries of Mayville Engineering Company, Inc. (Wisconsin) Name Domicile Center Manufacturing Holdings, Inc. Delaware Center Manufacturing, Inc. Delaware Center – Moeller Products LLC Delaware Defiance Metal Products Co. Ohio Defiance Metal Products of Arkansas, Inc. Arkansas Defiance Metal Products of PA., Inc. Pennsylvania Defiance Metal Products of WI, Inc. Wisconsin Mid-States A

MAYVILLE ENGINEERING COMPANY ANNOUNCES FOURTH QUARTER AND FULL-YEAR 2024 RESULTS

Exhibit 99 MAYVILLE ENGINEERING COMPANY ANNOUNCES FOURTH QUARTER AND FULL-YEAR 2024 RESULTS MILWAUKEE, Wis.

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 4, 2025 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation) (

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 20, 2025 Mayville Engine

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 20, 2025 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or Other Jurisdiction of Incorporatio

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): December 11, 2024 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation) (Commission

MAYVILLE ENGINEERING COMPANY ANNOUNCES LEADERSHIP TRANSITION

Exhibit 99 MAYVILLE ENGINEERING COMPANY ANNOUNCES LEADERSHIP TRANSITION MILWAUKEE, Wis.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2024 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38894 Mayville Engineering Company, Inc.

MAYVILLE ENGINEERING COMPANY ANNOUNCES THIRD QUARTER 2024 RESULTS

Exhibit 99 MAYVILLE ENGINEERING COMPANY ANNOUNCES THIRD QUARTER 2024 RESULTS MILWAUKEE, Wis.

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 5, 2024 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2024 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38894 Mayville Engineering Company, Inc.

MAYVILLE ENGINEERING COMPANY ANNOUNCES SECOND QUARTER 2024 RESULTS

Exhibit 99 MAYVILLE ENGINEERING COMPANY ANNOUNCES SECOND QUARTER 2024 RESULTS MILWAUKEE, Wis.

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 6, 2024 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 11-K FOR ANNUAL REPORTS OF EMPLOYEE STOCK PURCHASE, SAVINGS AND SIMILAR PLANS PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 11-K FOR ANNUAL REPORTS OF EMPLOYEE STOCK PURCHASE, SAVINGS AND SIMILAR PLANS PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2023 OR ☐ TRANSITION REPORT PUR

MAYVILLE ENGINEERING COMPANY, INC. 135 South 84th Street, Suite 300 Milwaukee, Wisconsin 53214 (414) 381-2860 May 15, 2024

MAYVILLE ENGINEERING COMPANY, INC. 135 South 84th Street, Suite 300 Milwaukee, Wisconsin 53214 (414) 381-2860 May 15, 2024 VIA EDGAR Division of Corporation Finance Office of Manufacturing U.S. Securities and Exchange Commission 100 F Street, N.E. Washington, D.C. 20549 Re:Mayville Engineering Company, Inc. Registration Statement on Form S-3 (Registration No. 333-277747) Ladies and Gentlemen: Purs

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2024 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38894 Mayville Engineering Company, Inc.

As filed with the Securities and Exchange Commission on May 8, 2024

Table of Contents As filed with the Securities and Exchange Commission on May 8, 2024 Registration No.

MAYVILLE ENGINEERING COMPANY ANNOUNCES FIRST QUARTER 2024 RESULTS

Exhibit 99 MAYVILLE ENGINEERING COMPANY ANNOUNCES FIRST QUARTER 2024 RESULTS MILWAUKEE, Wis.

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 7, 2024 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation) (Co

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 16, 2024 Mayville Engineeri

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 16, 2024 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation)

As filed with the Securities and Exchange Commission on March 7, 2024

Table of Contents As filed with the Securities and Exchange Commission on March 7, 2024 Registration No.

Form of Indenture

Exhibit 4.3 MAYVILLE ENGINEERING COMPANY, INC. to [*], Trustee INDENTURE Dated as of [*], 20 Debt Securities TABLE OF CONTENTS* Page Parties 1 Recitals 1 ARTICLE 1. DEFINITIONS 1 SECTION 1.01. Definitions 1 ARTICLE 2. DEBT SECURITY FORMS. 9 SECTION 2.01. Forms Generally 9 SECTION 2.02. Forms of Debt Securities 9 SECTION 2.03. Form of Trustee’s Certificate of Authentication 10 SECTION 2.04. Debt Se

Filing Fee Table.

Exhibit 107 Calculation of Filing Fee Table FORM S-3 REGISTRATION STATEMENT (Form Type) MAYVILLE ENGINEERING COMPANY, INC.

List of Subsidiaries of Mayville Engineering Company, Inc.

Exhibit 21 Subsidiaries of Mayville Engineering Company, Inc. (Wisconsin) Name Domicile Center Manufacturing Holdings, Inc. Delaware Center Manufacturing, Inc. Delaware Center – Moeller Products LLC Delaware Defiance Metal Products Co. Ohio Defiance Metal Products of Arkansas, Inc. Arkansas Defiance Metal Products of PA., Inc. Pennsylvania Defiance Metal Products of WI, Inc. Wisconsin Mid-States A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2023 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM TO Commission File Number 001-388

Form of Performance Stock Unit Award Agreement (Employee) under the Mayville Engineering Company, Inc. 2019 Omnibus Incentive Plan

Exhibit 10.17 MAYVILLE ENGINEERING COMPANY, INC. 2019 OMNIBUS INCENTIVE PLAN PERFORMANCE STOCK UNIT AWARD (EMPLOYEE FORM) [PARTICIPANTID] [FIRSTNAME] [LASTNAME] You have been granted an award of Performance Stock Units (this “Award”) of Mayville Engineering Company, Inc. (the “Company”) under the Mayville Engineering Company, Inc. 2019 Omnibus Incentive Plan (the “Plan”), effective as of the Grant

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. )

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)

Mayville Engineering Company, Inc. Compensation Recovery Policy.

Exhibit 97 Mayville Engineering Company, Inc. Compensation Recovery Policy 1. Purpose. The purpose of this Compensation Recovery Policy (this “Policy”) is to describe the circumstances under which Mayville Engineering Company, Inc. (the “Company”) is required to recover certain compensation paid to certain employees. Any references in compensation plans, agreements, equity awards or other policies

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 5, 2024 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation) (

MAYVILLE ENGINEERING COMPANY ANNOUNCES FOURTH QUARTER AND FULL-YEAR 2023 RESULTS

Exhibit 99 MAYVILLE ENGINEERING COMPANY ANNOUNCES FOURTH QUARTER AND FULL-YEAR 2023 RESULTS MILWAUKEE, Wis.

MEC / Mayville Engineering Company, Inc. / Allspring Global Investments Holdings, LLC Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 2) MAYVILLE ENGINEERING CO INC (Name of Issuer) COM (Title of Class of Securities) 578605107 (CUSIP Number) December 31, 2023 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Sched

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 2, 2023 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation) (Commission F

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2023 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38894 Mayville Engineering Company, Inc.

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 31, 2023 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation

MAYVILLE ENGINEERING COMPANY ANNOUNCES THIRD QUARTER 2023 RESULTS

EX-99 2 tmb-20231031xex99.htm EX-99 Exhibit 99 MAYVILLE ENGINEERING COMPANY ANNOUNCES THIRD QUARTER 2023 RESULTS MAYVILLE, Wis., October 31, 2023 - Mayville Engineering Company (NYSE: MEC) (the “Company” or “MEC”), a leading value-added provider of design, prototyping and manufacturing solutions serving diverse end-markets, today announced results for the three months ended September 30, 2023. THI

UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL INFORMATION

Exhibit 99.3 UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL INFORMATION On July 1, 2023, Mayville Engineering Company, Inc. (MEC, the Company, we, our, us or similar terms) completed its acquisition (the Acquisition) of Mid-States Aluminum (MSA) for $90.0 million in cash, which included estimated adjustments for the amount of cash, indebtedness, net working capital, and certain expenses of MSA a

Table of Contents

Exhibit 99.1 Mid-States Aluminum Corp. Financial Statements Year Ended December 31, 2022 Table of Contents Page Independent Auditor’s Report 2 FINANCIAL INFORMATION 4 Financial Statements (Audited) 4 Balance Sheet 4 Statement of Income 5 Statement of Stockholders’ Equity 6 Statement of Cash Flows 7 Notes to Audited Financial Statements 8 Independent Auditor’s Report Board of Directors Mid-States A

Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K/A (AMENDMENT NO.1) CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 1, 2023 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction o

Table of Contents

Exhibit 99.2 Mid-States Aluminum Corp. Interim Financial Statements Six months Ended June 30, 2023 Table of Contents Page FINANCIAL INFORMATION 2 Financial Statements (Unaudited) 2 Condensed Balance Sheet 2 Condensed Statement of Income 3 Condensed Statement of Cash Flows 4 Condensed Statement of Stockholders’ Equity 5 Notes to Unaudited Condensed Financial Statements 6 Mid-States Aluminum Corp. C

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2023 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38894 Mayville Engineering Company, Inc.

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 1, 2023 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation)

MAYVILLE ENGINEERING COMPANY ANNOUNCES SECOND QUARTER 2023 RESULTS

Exhibit 99 MAYVILLE ENGINEERING COMPANY ANNOUNCES SECOND QUARTER 2023 RESULTS MAYVILLE, Wis.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 1, 2023 Mayville Engineering

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 1, 2023 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation) (C

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 28, 2023 Mayville Engineerin

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 28, 2023 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation) (

Amended and Restated Credit Agreement, dated as of June 28, 2023, by and among Mayville Engineering Company, Inc., certain subsidiaries of Mayville Engineering Company, Inc. as guarantors, the lenders from time to time party thereto, and Wells Fargo Bank, National Association, as Administrative Agent for the lenders (incorporated by reference to Exhibit 10 to the Company’s Current Report on Form 8-K filed on June 29, 2023).

Exhibit 10 Published CUSIP Number: 57859VAP8‌ ‌ $250,000,000.00 AMENDED AND RESTATED CREDIT AGREEMENT dated as of June 28, 2023, by and among MAYVILLE ENGINEERING COMPANY, INC. as Borrower, the Lenders referred to herein, as Lenders, and WELLS FARGO BANK, NATIONAL ASSOCIATION, as Administrative Agent, Swingline Lender and Issuing Lender and WELLS FARGO SECURITIES, LLC, as Joint Lead Arranger and J

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 11-K FOR ANNUAL REPORTS OF EMPLOYEE STOCK PURCHASE, SAVINGS AND SIMILAR PLANS PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 11-K FOR ANNUAL REPORTS OF EMPLOYEE STOCK PURCHASE, SAVINGS AND SIMILAR PLANS PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2022 OR ☐ TRANSITION REPORT PUR

Unit Purchase Agreement, dated as of June 19, 2023, among Mayville Engineering Company, Inc. and the shareholders of Mid-States Aluminum Corp. (incorporated by reference to Exhibit 2 to the Current Report on Form 8-K filed on June 21, 2023) [The disclosure schedules and similar attachments to this agreement are not being filed herewith. The registrant agrees to furnish supplementally a copy of any such schedules or attachments to the Security and Exchange Commission upon request.]

Exhibit 2 UNIT PURCHASE AGREEMENT AMONG MAYVILLE ENGINEERING COMPANY, INC. AND THE SHAREHOLDERS OF MID-STATES ALUMINUM CORP. June 19, 2023 TABLE OF CONTENTS Page Article 1 purchase and sale of UNITS‌1 Article 2 PURCHASE PRICE; PAYMENT‌1 Section 2.1Closing Equity Value‌1 Section 2.2Purchase Price‌2 Section 2.3Payments.‌2 Section 2.4Adjustment Amount‌3 Section 2.5Withholding‌4 Article 3 REPRESENTATI

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 19, 2023 Mayville Engineerin

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 19, 2023 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation) (

MAYVILLE ENGINEERING COMPANY ANNOUNCES DEFINITIVE AGREEMENT TO ACQUIRE MID-STATES ALUMINUM CORP. Acquisition to provide MEC strategic capabilities expansion within lightweight materials Acquisition expected to be immediately accretive, excluding tran

Exhibit 99 MAYVILLE ENGINEERING COMPANY ANNOUNCES DEFINITIVE AGREEMENT TO ACQUIRE MID-STATES ALUMINUM CORP.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2023 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38894 Mayville Engineering Company, Inc.

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 2, 2023 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation) (Co

MAYVILLE ENGINEERING COMPANY ANNOUNCES FIRST QUARTER AND 2023 RESULTS

Exhibit 99 MAYVILLE ENGINEERING COMPANY ANNOUNCES FIRST QUARTER AND 2023 RESULTS MAYVILLE, Wis.

Amendment to Bylaws of Mayville Engineering Company, Inc. effective April 18, 2023.

Exhibit 3.1 AMENDMENT TO the second sentence of SECTION 3.01 OF ARTICLE III OF THE BYLAWS OF Mayville engineering company, INC. Effective April 18, 2023 (Additions in bold and underscore; deletions in strikethrough) The number of directors of the corporation shall be eight (8) seven (7), divided into three classes, designated as Class I, Class II and Class III; and such classes shall consist, as n

Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year, Financial Statements and Exhibits, Submission of Matters to a Vote of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 18, 2023 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation)

Bylaws of Mayville Engineering Company, Inc., as amended through April 18, 2023 (incorporated by reference to Exhibit 3.2 to the Company’s Current Report on Form 8-K filed on April 19, 2023).

Exhibit 3.2 BYLAWS OF MAYVILLE ENGINEERING COMPANY, INC. (a Wisconsin corporation) Effective 5/13/19 Amended 3/30/2020, 5/12/2020, 12/3/2020, 4/20/2021, 12/21/2022 and 4/18/2023 ARTICLE I. OFFICES 1.01Principal and Business Offices. The corporation may have such principal and other business offices, either within or without the State of Wisconsin, as the Board of Directors may designate or as the

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. )

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2022 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM TO Commission File Number 001-388

List of Subsidiaries of Mayville Engineering Company, Inc.

Exhibit 21 Subsidiaries of Mayville Engineering Company, Inc. (Wisconsin) Name Domicile Center Manufacturing Holdings, Inc. Delaware Center Manufacturing, Inc. Delaware Center – Moeller Products LLC Delaware Defiance Metal Products Co. Ohio Defiance Metal Products of Arkansas, Inc. Arkansas Defiance Metal Products of PA., Inc. Pennsylvania Defiance Metal Products of WI, Inc. Wisconsin

MAYVILLE ENGINEERING COMPANY ANNOUNCES FOURTH QUARTER AND FULL-YEAR 2022 RESULTS

Exhibit 99 MAYVILLE ENGINEERING COMPANY ANNOUNCES FOURTH QUARTER AND FULL-YEAR 2022 RESULTS MAYVILLE, Wis.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 28, 2023 Mayville Engine

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 28, 2023 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporatio

MEC / Mayville Engineering Company Inc / Allspring Global Investments Holdings, LLC Passive Investment

SC 13G/A 1 Mayvilleeng578605107.htm UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 2) MAYVILLE ENGINEERING CO INC (Name of Issuer) COM (Title of Class of Securities) 578605107 (CUSIP Number) December 31, 2022 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate t

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year, Financial Statements and Exhibits

? ? UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): December 21, 2022 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorpor

MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES APPOINTMENT OF ROBERT McCORMICK TO BOARD OF DIRECTORS

Exhibit 99 ? ? MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES APPOINTMENT OF ROBERT McCORMICK TO BOARD OF DIRECTORS ? Mayville, WI ? December 21, 2022 ? Mayville Engineering Company (NYSE: MEC) (the ?Company? or ?MEC?), a leading U.S.-based value-added manufacturing partner that provides a full suite of services from concept to production today announced that the Board of Directors has elected Rober

Bylaws of Mayville Engineering Company, Inc., as amended through December 21, 2022.

Exhibit 3.2 ? BYLAWS ? OF ? MAYVILLE ENGINEERING COMPANY, INC. (a Wisconsin corporation) ? ? ? ? ? ? ? ? ? ? ? ? ? ? Effective 5/13/19 Amended 3/30/2020, 5/12/2020, 12/3/2020, 4/20/2021 and 12/21/2022 ? ? ? ? ? ARTICLE I. OFFICES 1.01Principal and Business Offices. The corporation may have such principal and other business offices, either within or without the State of Wisconsin, as the Board of D

Amendment to the Bylaws of Mayville Engineering Company, Inc effective December 21, 2022.

Exhibit 3.1 AMENDMENT TO the second sentence of SECTION 3.01 OF ARTICLE III OF THE BYLAWS OF Mayville engineering company, INC. Effective December 21, 2022 (Additions in bold and underscore; deletions in strikethrough) ? The number of directors of the corporation shall be seven (7) eight (8), divided into three classes, designated as Class I, Class II and Class III; and such classes shall consist,

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q

Table of Contents ? UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2022 OR ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38894 Mayville Engineering Company, Inc.

MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES THIRD QUARTER 2022 RESULTS Delivered Significant Top- and Bottom-Line Year-over-Year Improvements Across All Metrics; Commenced Production at state-of-the-art Hazel Park, Michigan Facility as Planned

Exhibit 99 MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES THIRD QUARTER 2022 RESULTS Delivered Significant Top- and Bottom-Line Year-over-Year Improvements Across All Metrics; Commenced Production at state-of-the-art Hazel Park, Michigan Facility as Planned Mayville, WI/November 1, 2022/Mayville Engineering Company (NYSE: MEC) (the ?Company? or ?MEC?), a leading U.S.-based value-added manufacturing

Financial Statements and Exhibits, Results of Operations and Financial Condition

? ? UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 1, 2022 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorpora

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2022 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38894 Mayville Engineering Company, Inc.

MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES SECOND QUARTER 2022 RESULTS Company Produces Significant Bottom Line Growth and Reiterates 2022 Guidance

Exhibit 99 MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES SECOND QUARTER 2022 RESULTS Company Produces Significant Bottom Line Growth and Reiterates 2022 Guidance Mayville, WI/August 2, 2022/Mayville Engineering Company (NYSE: MEC) (the “Company” or “MEC”), a leading U.S.-based value-added manufacturing partner that provides a full suite of prototyping and tooling, production fabrication, coating, a

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 2, 2022 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation)

Form of Change in Control Employment and Severance Agreement between Mayville Engineering Company, Inc. and Jagadeesh A. Reddy (incorporated by reference to Exhibit 10.2 to the Company’s Current Report on Form 8-K filed on July 20, 2022).

? Exhibit 10.2 CHANGE IN CONTROL EMPLOYMENT AND SEVERANCE AGREEMENT THIS CHANGE IN CONTROL EMPLOYMENT AND SEVERANCE AGREEMENT, effective as of the day of , 2022 (this ?Agreement?), is by and between MAYVILLE ENGINEERING COMPANY, INC., a Wisconsin corporation (the ?Company?), and JAGADEESH A. REDDY (the ?Executive?). WITNESSETH: WHEREAS, the Executive has agreed to serve as the Company?s President

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

? ? UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 19, 2022 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporatio

Form of Severance Agreement between Mayville Engineering Company, Inc. and each of Ryan F. Raber, Sean P. Leuba and Rachele M. Lehr (incorporated by reference to Exhibit 10.3 to the Company’s Current Report on Form 8-K filed on July 20, 2022).

Exhibit 10.3 SEVERANCE AGREEMENT THIS SEVERANCE AGREEMENT, effective as of the [] day of [], 2022 (this ?Agreement?), is by and between MAYVILLE ENGINEERING COMPANY, INC. a Wisconsin corporation (the ?Company?), and [] (the ?Executive?). WITNESSETH: WHEREAS, the Executive is currently serving as the Company?s [POSITION]. WHEREAS, the Company is currently party to a Change in Control Employment and

MEC Announces Appointment of Jag A. Reddy as President & CEO Current Independent Director Timothy L. Christen Named Non-Executive Chair

Exhibit 99 ? ? MEC Announces Appointment of Jag A. Reddy as President & CEO Current Independent Director Timothy L. Christen Named Non-Executive Chair ? MAYVILLE, Wis. July 20, 2022 ? Mayville Engineering Company (NYSE: MEC) (the ?Company? or ?MEC?), a leading U.S.-based value-added manufacturing partner that provides a full suite of design, prototyping, tooling, production fabrication, coatings,

Form of Severance Agreement between Mayville Engineering Company, Inc. and Jagadeesh A. Reddy (incorporated by reference to Exhibit 10.1 to the Company’s Current Report on Form 8-K filed on July 20, 2022).

? Exhibit 10.1 SEVERANCE AGREEMENT THIS SEVERANCE AGREEMENT, effective as of the day of , 2022 (this ?Agreement?), is by and between MAYVILLE ENGINEERING COMPANY, INC. a Wisconsin corporation (the ?Company?), and JAGADEESH A. REDDY (the ?Executive?). WITNESSETH: WHEREAS, the Executive has agreed to serve as the Company?s President and Chief Executive Officer. WHEREAS, the Company desires to provid

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 11-K FOR ANNUAL REPORTS OF EMPLOYEE STOCK PURCHASE, SAVINGS AND SIMILAR PLANS PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

Table of Contents ? UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q

Table of Contents ? UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2022 OR ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38894 Mayville Engineering Company, Inc.

Financial Statements and Exhibits, Results of Operations and Financial Condition

? ? UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 3, 2022 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation)

MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES FIRST QUARTER 2022 RESULTS Effective Execution Delivers Top and Bottom-Line Growth

Exhibit 99 MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES FIRST QUARTER 2022 RESULTS Effective Execution Delivers Top and Bottom-Line Growth Mayville, WI/May 3, 2022/Mayville Engineering Company (NYSE: MEC) (the ?Company? or ?MEC?), a leading U.S.-based value added manufacturing partner that provides a broad range of prototyping and tooling, production fabrication, coating, assembly and aftermarket

Submission of Matters to a Vote of Security Holders

? ? UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 19, 2022 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporati

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. )

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Defin

Agreement on Confidentiality, Assignment of Intellectual Property, Non-Competition and Non-Solicitation, dated as of March 31, 2022, by and between Mayville Engineering Company, Inc. and Robert D. Kamphuis (incorporated by reference to Exhibit 10.2 to the Company’s Current Report on Form 8-K filed on April 1, 2022).

EXHIBIT 10.2 AGREEMENT ON CONFIDENTIALITY, Trade secrets, assignment of intellectual property, Competition and non-solicitation THIS AGREEMENT ON CONFIDENTIALITY, TRADE SECRETS, ASSIGNMENT OF INTELLECTUAL PROPERTY, COMPETITION AND NON-SOLICITATION (this ?Agreement?) is entered into by and between Mayville Engineering Company, Inc. (?MEC? or the ?Company?), and the employee identified on the signat

Retirement Transition Agreement, dated as of March 31, 2022, by and between Mayville Engineering Company, Inc. and Robert D. Kamphuis (incorporated by reference to Exhibit 10.1 to the Company’s Current Report on Form 8-K filed on April 1, 2022).

EXHIBIT 10.1 RETIREMENT AGREEMENT This Agreement is between Mayville Engineering Company, Inc. (which in this Agreement is referred to as ?MEC? or ?the Company?) and Robert Kamphuis, who is referred to as ?Employee? or ?Mr. Kamphuis.? 1.Background. Mr. Kamphuis has advised MEC that he would like to retire from MEC, and has identified a retirement date, which will end his employment with MEC, effec

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 31, 2022 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation)

MEC Announces Retirement Plan of CEO Robert D. Kamphuis Kamphuis to Retire on September 30, 2022 After 17 years as CEO

EXHIBIT 99 MEC Announces Retirement Plan of CEO Robert D. Kamphuis Kamphuis to Retire on September 30, 2022 After 17 years as CEO Mayville, WI ? March 31, 2022 ? Mayville Engineering Company, Inc. (NYSE: MEC) (?MEC?), a leading U.S.-based value added manufacturing partner that provides a broad range of prototyping and tooling, production fabrication, coating, assembly and aftermarket services, tod

Fourth Amendment, dated as of March 31, 2022, to the Amended and Restated Credit Agreement, dated as of September 26, 2019, by and among Mayville Engineering Company, Inc., the lenders from time to time party thereto, and Wells Fargo Bank, National Association, as Administrative Agent for the lenders.

EXHIBIT 10 FOURTH AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT THIS FOURTH AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT is made as of March 31, 2022 (the ?Fourth Amendment Effective Date?), by and among MAYVILLE ENGINEERING COMPANY, INC.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. )

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Defin

Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 31, 2022 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. )

DEF 14A 1 d290297ddef14a.htm DEF 14A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as p

List of Subsidiaries of Mayville Engineering Company, Inc.

Exhibit 21 Subsidiaries of Mayville Engineering Company, Inc. (Wisconsin) Name Domicile Center Manufacturing Holdings, Inc. Delaware Center Manufacturing, Inc. Delaware Center ? Moeller Products LLC Delaware Defiance Metal Products Co. Ohio Defiance Metal Products of Arkansas, Inc. Arkansas Defiance Metal Products of PA., Inc. Pennsylvania Defiance Metal Products of WI, Inc. Wisconsin

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 1, 2022 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation) (

MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES FOURTH QUARTER AND FULL YEAR 2021 RESULTS Improved Full Year 2021 Results Bode Well for 2022

Exhibit 99 MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES FOURTH QUARTER AND FULL YEAR 2021 RESULTS Improved Full Year 2021 Results Bode Well for 2022 Mayville, WI/March 1, 2022/Mayville Engineering Company (NYSE: MEC) (the ?Company? or ?MEC?), a leading U.S.-based value added manufacturing partner that provides a broad range of prototyping and tooling, production fabrication, coating, assembly and

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ? ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2021 OR ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM TO Commission File Number 001-38894 Mayville Engine

MEC / Mayville Engineering Company Inc / PRUDENTIAL FINANCIAL INC Passive Investment

13G HTML File DOCUMENT TYPE SC 13G/A TEXT SECURITIES AND EXCHANGE COMMISSION Washington, D.

MAYVILLE ENGINEERING COMPANY PROVIDES BUSINESS UPDATE Company Narrows 2021 Outlook, Reviews End Markets, Gives Fitness Customer Update and Provides 2022 Guidance

EX-99 2 mec-ex997.htm EX-99 Exhibit 99 MAYVILLE ENGINEERING COMPANY PROVIDES BUSINESS UPDATE Company Narrows 2021 Outlook, Reviews End Markets, Gives Fitness Customer Update and Provides 2022 Guidance MAYVILLE, Wis. Mayville Engineering Company (NYSE: MEC) (the “Company” or “MEC”), a leading U.S.-based value added manufacturing partner that provides a broad range of prototyping and tooling, produc

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 9, 2022 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation

MEC / Mayville Engineering Company Inc / WELLINGTON MANAGEMENT GROUP LLP - SEC SCHEDULE 13G Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 1 )* Mayville Engineering Company, Inc. (Name of Issuer) Common Stock (Title of Class of Securities) 578605107 (CUSIP Number) December 31, 2021 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant t

MEC / Mayville Engineering Company Inc / Allspring Global Investments Holdings, LLC Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. ) MAYVILLE ENGINEERING CO INC (Name of Issuer) COM (Title of Class of Securities) 578605107 (CUSIP Number) December 31, 2021 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Schedu

MEC / Mayville Engineering Company Inc / Allspring Global Investments Holdings, LLC Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. ) MAYVILLE ENGINEERING CO INC (Name of Issuer) COM (Title of Class of Securities) 578605107 (CUSIP Number) November 30, 2021 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Schedu

MEC / Mayville Engineering Company Inc / WELLS FARGO & COMPANY/MN Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 3) MAYVILLE ENGR CO INC (Name of Issuer) COM (Title of Class of Securities) 578605107 (CUSIP Number) November 30, 2021 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Schedule is

MEC / Mayville Engineering Company Inc / WELLS FARGO & COMPANY/MN Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 2) MAYVILLE ENGR CO INC (Name of Issuer) COM (Title of Class of Securities) 578605107 (CUSIP Number) October 31, 2021 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Schedule is f

As filed with the Securities and Exchange Commission on November 4, 2021

As filed with the Securities and Exchange Commission on November 4, 2021 Registration No.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2021 OR ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38894 Mayville Engineering Company, Inc.

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 2, 2021 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation

MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES THIRD QUARTER 2021 RESULTS

Exhibit 99 MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES THIRD QUARTER 2021 RESULTS Mayville, WI/November 2, 2021/Mayville Engineering Company (NYSE: MEC) (the ?Company? or ?MEC?), a leading U.S.-based value-added manufacturing partner that provides a broad range of prototyping and tooling, production fabrication, coating, assembly and aftermarket components, today announced results for the third q

MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES SECOND QUARTER 2021 RESULTS Ongoing Strong Demand Across End Markets Drives Results

EX-99 2 d197701dex99.htm EX-99 Exhibit 99 MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES SECOND QUARTER 2021 RESULTS Ongoing Strong Demand Across End Markets Drives Results Mayville, WI/August 3, 2021/Mayville Engineering Company (NYSE: MEC) (the “Company” or “MEC”), a leading U.S.-based value-added manufacturing partner that provides a broad range of prototyping and tooling, production fabrication,

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 3, 2021 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2021 OR ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38894 Mayville Engineering Company, Inc.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 11-K FOR ANNUAL REPORTS OF EMPLOYEE STOCK PURCHASE, SAVINGS AND SIMILAR PLANS PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 11-K FOR ANNUAL REPORTS OF EMPLOYEE STOCK PURCHASE, SAVINGS AND SIMILAR PLANS PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 (Mark One) ? ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2020 OR ? TRANSITION REPORT PURSUANT TO SECTION 1

Mayville Engineering Company, Inc. 715 South Street Mayville, Wisconsin 53050 May 14, 2021

Mayville Engineering Company, Inc. 715 South Street Mayville, Wisconsin 53050 May 14, 2021 Via EDGAR and Email to [email protected] Ms. Mindy Hooker Mr. Kevin Stertzel Office of Manufacturing Division of Corporation Finance United States Securities and Exchange Commission 100 F Street, N.E. Washington, D.C. 20549 Re:Mayville Engineering Company, Inc. Form 10-K/A for the year ended December 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K/A Amendment No. 2

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K/A Amendment No. 2 (Mark One) ? ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2020 OR ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM TO Commission File Number 001-388

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 4, 2021 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation) (Co

MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES FIRST QUARTER 2021 RESULTS Strong Performance Driven by Improving Economic Climate and End Market Demand, Plus Cost Optimizing Initiatives

Exhibit 99 MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES FIRST QUARTER 2021 RESULTS Strong Performance Driven by Improving Economic Climate and End Market Demand, Plus Cost Optimizing Initiatives Mayville, WI/May 4, 2021/Mayville Engineering Company (NYSE: MEC) (the ?Company? or ?MEC?), a leading U.S.-based value-added manufacturing partner that provides a broad range of prototyping and tooling, pr

Quarterly Report - 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2021 OR ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38894 Mayville Engineering Company, Inc.

Mayville Engineering Company, Inc. 715 South Street Mayville, Wisconsin 53050 May 3, 2021

Mayville Engineering Company, Inc. 715 South Street Mayville, Wisconsin 53050 May 3, 2021 Via EDGAR and email [email protected] Ms. Mindy Hooker Mr. Kevin Stertzel Office of Manufacturing Division of Corporation Finance United States Securities and Exchange Commission 100 F Street, N.E. Washington, D.C. 20549 Re:Mayville Engineering Company, Inc. Form 10-K for the year ended December 31, 202

Annual Report - 10-K/A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K/A Amendment No. 1 (Mark One) ? ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2020 OR ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM TO Commission File Number 001-388

Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year, Financial Statements and Exhibits, Submission of Matters to a Vote of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 20, 2021 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation)

Amendment to the Bylaws of Mayville Engineering Company, Inc. effective April 20, 2021.

Exhibit 3.1 AMENDMENT TO THE SECOND SENTENCE OF SECTION 3.01 OF ARTICLE III OF THE BYLAWS OF MAYVILLE ENGINEERING COMPANY, INC. Effective April 20, 2021 (Additions in bold and underscore; deletions in strikethrough) The number of directors of the corporation shall be eight (8) seven (7), divided into three classes, designated as Class I, Class II and Class III; and such classes shall consist, as n

Bylaws of Mayville Engineering Company, Inc., as amended through April 20, 2021.

Exhibit 3.2 BYLAWS OF MAYVILLE ENGINEERING COMPANY, INC. (a Wisconsin corporation) Effective 5/13/19 Amended 3/30/2020, 5/12/2020, 12/3/2020 and 4/20/2021 ARTICLE I. OFFICES 1.01 Principal and Business Offices. The corporation may have such principal and other business offices, either within or without the State of Wisconsin, as the Board of Directors may designate or as the business of the corpor

Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 31, 2021 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation)

Third Amendment, dated as of March 31, 2021, to the Amended and Restated Credit Agreement, dated as of September 26, 2019, by and among Mayville Engineering Company, Inc., the lenders from time to time party thereto, Wells Fargo Bank, National Association, as Administrative Agent for the lenders, and Wells Fargo Securities, LLC, as Sole Lead Arranger and Sole Bookrunner.

Exhibit 10 THIRD AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT THIS THIRD AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT is made as of March 31, 2021 (the ?Third Amendment Effective Date?), by and among MAYVILLE ENGINEERING COMPANY, INC.

Mayville Engineering Company, Inc. 2019 Omnibus Incentive Plan, as amended through April 20, 2021 (incorporated by reference to Appendix A to the Registrant’s Definitive Proxy Statement on Schedule 14A filed on March 8, 2021).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Defin

List of Subsidiaries of Mayville Engineering Company, Inc.

Exhibit 21 Subsidiaries of Mayville Engineering Company, Inc. (Wisconsin) Name Domicile Center Manufacturing Holdings, Inc. Delaware Center Manufacturing, Inc. Delaware Center ? Moeller Products LLC Delaware Defiance Metal Products Co. Ohio Defiance Metal Products of Arkansas, Inc. Arkansas Defiance Metal Products of PA., Inc. Pennsylvania Defiance Metal Products of WI, Inc. Wisconsin 4812-1893-15

Annual Report - 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ? ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2020 OR ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM TO Commission File Number 001-38894 Mayville Engine

MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES FOURTH QUARTER AND FULL YEAR 2020 RESULTS Strong Fourth Quarter Financial Performance Driven by Generally Improved Operating Conditions and Profitability Improvements; Utilized Strong Cash Flow Generation

Exhibit 99 MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES FOURTH QUARTER AND FULL YEAR 2020 RESULTS Strong Fourth Quarter Financial Performance Driven by Generally Improved Operating Conditions and Profitability Improvements; Utilized Strong Cash Flow Generation to Further Reduce Debt Mayville, WI/March 2, 2021/Mayville Engineering Company (NYSE: MEC) (the ?Company? or ?MEC?), a leading U.S.-based v

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 2, 2021 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation) (

SCHEDULE 13G SIGNATURE

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 1) MAYVILLE ENGINEERING CO INC (Name of Issuer) COM (Title of Class of Securities) 578605107 (CUSIP Number) December 31, 2020 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Sched

By signing below, Prudential Financial, Inc. certifies that, to the best of its

13G HTML File DOCUMENT TYPE SC 13G TEXT SECURITIES AND EXCHANGE COMMISSION Washington, D.

SCHEDULE 13G

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. )* Mayville Engineering Company, Inc. (Name of Issuer) Common Stock (Title of Class of Securities) 578605107 (CUSIP Number) December 31, 2020 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year, Financial Statements and Exhibits - 8-K

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): December 3, 2020 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorpora

Bylaws of Mayville Engineering Company, Inc., as amended through December 3, 2020.

EX-3.2 3 d50641dex32.htm EX-3.2 Exhibit 3.2 BYLAWS OF MAYVILLE ENGINEERING COMPANY, INC. (a Wisconsin corporation) Effective 5/13/19 Amended 3/30/2020, 5/12/2020 and 12/3/2020 ARTICLE I. OFFICES 1.01 Principal and Business Offices. The corporation may have such principal and other business offices, either within or without the State of Wisconsin, as the Board of Directors may designate or as the b

Amendment to the Bylaws of Mayville Engineering Company, Inc. effective December 3, 2020.

EX-3.1 Exhibit 3.1 AMENDMENT TO THE SECOND SENTENCE OF SECTION 3.01 OF ARTICLE III OF THE BYLAWS OF MAYVILLE ENGINEERING COMPANY, INC. Effective December 3, 2020 (Additions in bold and underscore; deletions in strikethrough) The number of directors of the corporation shall be seven (7) eight (8), divided into three classes, designated as Class I, Class II and Class III; and such classes shall cons

MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES APPOINTMENT OF JENNIFER KENT TO BOARD OF DIRECTORS Current Director Craig E. Johnson to Retire in 2021

EX-99 4 d50641dex99.htm EX-99 Exhibit 99 MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES APPOINTMENT OF JENNIFER KENT TO BOARD OF DIRECTORS Current Director Craig E. Johnson to Retire in 2021 Mayville, WI — Dec 3, 2020 — Mayville Engineering Company, Inc. (NYSE: MEC) (“MEC”) today announced that the Board of Directors has elected Jennifer Kent as a director of the Company. The Company also announced

Financial Statements and Exhibits, Results of Operations and Financial Condition - 8-K

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 2, 2020 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorpora

Form of Change in Control Employment and Severance Agreement between Mayville Engineering Company, Inc. and each of Ryan F. Raber, Sean P. Leuba and Rachele M. Lehr (incorporated by reference to Exhibit 10.2 to the Company’s Quarterly Report on Form 10-Q filed on November 3, 2020).

Exhibit 10.2 CHANGE IN CONTROL EMPLOYMENT AND SEVERANCE AGREEMENT THIS CHANGE IN CONTROL EMPLOYMENT AND SEVERANCE AGREEMENT, effective as of the day of , 2020 (this “Agreement”), is by and between MAYVILLE ENGINEERING COMPANY, INC., a Wisconsin corporation (the “Company”), and (the “Executive”). W I T N E S S E T H WHEREAS, the Executive is employed by the Company and/or a subsidiary of the Compan

Form of Change in Control Employment and Severance Agreement between Mayville Engineering Company, Inc. and Todd M. Butz (incorporated by reference to Exhibit 10.1 to the Company’s Quarterly Report on Form 10-Q filed on November 3, 2020).

Exhibit 10.1 CHANGE IN CONTROL EMPLOYMENT AND SEVERANCE AGREEMENT THIS CHANGE IN CONTROL EMPLOYMENT AND SEVERANCE AGREEMENT, effective as of the day of , 2020 (this “Agreement”), is by and between MAYVILLE ENGINEERING COMPANY, INC., a Wisconsin corporation (the “Company”), and (the “Executive”). W I T N E S S E T H WHEREAS, the Executive is employed by the Company and/or a subsidiary of the Compan

MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES THIRD QUARTER 2020 RESULTS Sequential Improvement in Financial Performance; Further Debt Reduction Based on Cash Flow Strength

EX-99 Exhibit 99 MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES THIRD QUARTER 2020 RESULTS Sequential Improvement in Financial Performance; Further Debt Reduction Based on Cash Flow Strength Mayville, WI/November 2, 2020/Mayville Engineering Company (NYSE: MEC) (the “Company” or “MEC”), a leading U.S.-based value added manufacturing partner that provides a broad range of prototyping and tooling, pro

Quarterly Report - 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2020 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38894 Mayville Engineering Company, Inc.

- 11-K/A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 11-K/A (Amendment No. 1) FOR ANNUAL REPORTS OF EMPLOYEE STOCK PURCHASE, SAVINGS AND SIMILAR PLANS PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2019 OR ☐ TRANSITION REPORT P

Financial Statements and Exhibits, Results of Operations and Financial Condition

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 4, 2020 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporati

Quarterly Report - 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2020 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38894 Mayville Engineering Company, Inc.

MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES SECOND QUARTER 2020 RESULTS Effectively Managing Cost Structure to Enhance Long-Term Profitability

EX-99 Exhibit 99 MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES SECOND QUARTER 2020 RESULTS Effectively Managing Cost Structure to Enhance Long-Term Profitability Mayville, WI/August 4, 2020/Mayville Engineering Company (NYSE: MEC) (the “Company” or “MEC”), a leading U.S.-based value added manufacturing partner that provides a broad range of prototyping and tooling, production fabrication, coating,

- 11-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 11-K FOR ANNUAL REPORTS OF EMPLOYEE STOCK PURCHASE, SAVINGS AND SIMILAR PLANS PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2019 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 1

Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 30, 2020 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporatio

Second Amendment, dated as of June 30, 2020, to the Amended and Restated Credit Agreement, dated as of September 26, 2019, by and among Mayville Engineering Company, Inc., the lenders from time to time party thereto, Wells Fargo Bank, National Association, as Administrative Agent for the lenders, and Wells Fargo Securities, LLC, as Sole Lead Arranger and Sole Bookrunner.

EX-10 Exhibit 10 SECOND AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT THIS SECOND AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT is made as of June 30, 2020 (the “Second Amendment Effective Date”), by and among MAYVILLE ENGINEERING COMPANY, INC.

Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 25, 2020 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation) (

Bylaws of Mayville Engineering Company, Inc., as amended through May 12, 2020.

EX-3.2 Exhibit 3.2 BYLAWS OF MAYVILLE ENGINEERING COMPANY, INC. (a Wisconsin corporation) Effective 5/13/19 Amended 3/30/2020 and 5/12/2020 ARTICLE I. OFFICES 1.01 Principal and Business Offices. The corporation may have such principal and other business offices, either within or without the State of Wisconsin, as the Board of Directors may designate or as the business of the corporation may requi

Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year, Financial Statements and Exhibits, Submission of Matters to a Vote of Security Holders

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 12, 2020 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation

Amendment to the Bylaws of Mayville Engineering Company, Inc. effective May 12, 2020.

EX-3.1 Exhibit 3.1 AMENDMENT TO THE SECOND SENTENCE OF SECTION 3.01 OF ARTICLE III OF THE BYLAWS OF MAYVILLE ENGINEERING COMPANY, INC. Effective May 12, 2020 (Additions in bold and underscore; deletions in strikethrough) The number of directors of the corporation shall be eight (8) seven (7), divided into three classes, designated as Class I, Class II and Class III; and such classes shall consist,

MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES FIRST QUARTER 2020 RESULTS Generated Solid Cash Flow and Maintains Strong Financial Position

EX-99 Exhibit 99 MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES FIRST QUARTER 2020 RESULTS Generated Solid Cash Flow and Maintains Strong Financial Position Mayville, WI/May 5, 2020/Mayville Engineering Company (NYSE: MEC) (the “Company” or “MEC”), a leading U.S.-based value added manufacturing partner that provides a broad range of prototyping and tooling, production fabrication, coating, assembly

Quarterly Report - 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2020 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38894 Mayville Engineering Company, Inc.

Financial Statements and Exhibits, Results of Operations and Financial Condition

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 5, 2020 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation)

Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year, Financial Statements and Exhibits

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 30, 2020 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporati

MEC / Mayville Engineering Company, Inc. DEF 14A - - DEF 14A

DEF 14A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

Bylaws of Mayville Engineering Company, Inc., as amended through March 30, 2020.

EX-3.2 Exhibit 3.2 BYLAWS OF MAYVILLE ENGINEERING COMPANY, INC. (a Wisconsin corporation) Effective 5/13/19 Amended 3/30/2020 ARTICLE I. OFFICES 1.01 Principal and Business Offices. The corporation may have such principal and other business offices, either within or without the State of Wisconsin, as the Board of Directors may designate or as the business of the corporation may require from time t

Amendments to the Bylaws of Mayville Engineering Company, Inc. effective March 30, 2020.

EX-3.1 Exhibit 3.1 BYLAWS OF MAYVILLE ENGINEERING COMPANY, INC. (a Wisconsin corporation) Effective 5/13/19 Amended 3/30/2020 ARTICLE I. OFFICES 1.01 Principal and Business Offices. The corporation may have such principal and other business offices, either within or without the State of Wisconsin, as the Board of Directors may designate or as the business of the corporation may require from time t

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 12, 2020 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporati

MEC ANNOUNCES CHIEF OPERATING OFFICER TRANSITION Steve Mance to Retire Following Successful Integration of Defiance Metal Products (DMP) Current MEC EVP Rand Stille Promoted to COO

EX-99 Exhibit 99 MEC ANNOUNCES CHIEF OPERATING OFFICER TRANSITION Steve Mance to Retire Following Successful Integration of Defiance Metal Products (DMP) Current MEC EVP Rand Stille Promoted to COO Mayville, WI/March 12, 2020/Mayville Engineering Company (NYSE: MEC) (the “Company” or “MEC”), a leading U.

MEC / Mayville Engineering Company, Inc. 10-K - Annual Report - 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2019 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM TO Commission File Number 001-38894 Mayville Engine

List of Subsidiaries of Mayville Engineering Company, Inc.

Exhibit 21 Subsidiaries of Mayville Engineering Company, Inc. (Wisconsin) Name Domicile Center Manufacturing Holdings, Inc. Delaware Center Manufacturing, Inc. Delaware Center – Moeller Products LLC Delaware Defiance Metal Products Co. Ohio Defiance Metal Products of Arkansas, Inc. Arkansas Defiance Metal Products of PA., Inc. Pennsylvania Defiance Metal Products of WI, Inc. Wisconsin

Description of Mayville Engineering Company, Inc.’s Securities (incorporated by reference to Exhibit 4 to the Company’s Annual Report on Form 10-K filed on March 2, 2020).

Exhibit 4 mayville engineering company, inc. Description of securities Our amended and restated articles of incorporation provide that we have the authority to issue 75,000,000 shares of our common stock, no par value per share, and 5,000,000 shares of preferred stock, par value $0.01 per share. The following is a summary of the material provisions of our common stock and preferred stock. This sum

MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES FULL YEAR and FOURTH QUARTER 2019 RESULTS Performance Impacted by Sudden Demand Changes Starting in Late Third Quarter; Ends Year in Strong Financial Position

EX-99 Exhibit 99 MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES FULL YEAR and FOURTH QUARTER 2019 RESULTS Performance Impacted by Sudden Demand Changes Starting in Late Third Quarter; Ends Year in Strong Financial Position Mayville, WI/February 26, 2020/Mayville Engineering Company (NYSE: MEC) (the “Company” or “MEC”), a leading U.S.-based value-added manufacturing partner that provides a broad rang

Financial Statements and Exhibits, Results of Operations and Financial Condition

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 26, 2020 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorpor

MEC / Mayville Engineering Company, Inc. / WELLS FARGO & COMPANY/MN Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. ) MAYVILLE ENGINEERING CO INC (Name of Issuer) COM (Title of Class of Securities) 578605107 (CUSIP Number) December 31, 2019 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Schedu

Financial Statements and Exhibits, Other Events

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 23, 2020 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorpora

Form of Stock Option Award Agreement under the Mayville Engineering Company, Inc. 2019 Omnibus Incentive Plan (Full Term Exercise Period on Retirement) (incorporated by reference to Exhibit 10 to the Company’s Current Report on Form 8-K filed on January 29, 2020).

EX-10 Exhibit 10 Full-Term Exercise Period on Retirement MAYVILLE ENGINEERING COMPANY, INC.

Mayville Engineering Company (MEC) Provides 2020 Financial and Market Outlook Company Also Confirms 2019 Financial Outlook

EX-99 Exhibit 99 Mayville Engineering Company (MEC) Provides 2020 Financial and Market Outlook Company Also Confirms 2019 Financial Outlook Mayville, WI/January 29, 2020/Mayville Engineering Company, Inc.

Financial Statements and Exhibits, Results of Operations and Financial Condition

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 29, 2020 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorpora

MEC / Mayville Engineering Company, Inc. S-8 - - S-8

S-8 As filed with the Securities and Exchange Commission on November 5, 2019 Registration No.

MEC / Mayville Engineering Company, Inc. S-8 - - S-8

S-8 Table of Contents As filed with the Securities and Exchange Commission on November 5, 2019 Registration No.

September 30, 2019

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2019 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38894 Mayville Engineering Company, Inc.

Financial Statements and Exhibits, Results of Operations and Financial Condition

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 29, 2019 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorpora

MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES THIRD QUARTER 2019 RESULTS Performance & Outlook Impacted by Near-Term Market Demand Changes; Integration of Former Defiance Metal Products (“DMP”) Nearing Completion

EX-99 Exhibit 99 MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES THIRD QUARTER 2019 RESULTS Performance & Outlook Impacted by Near-Term Market Demand Changes; Integration of Former Defiance Metal Products (“DMP”) Nearing Completion Mayville, WI/October 29, 2019/Mayville Engineering Company (NYSE: MEC) (the “Company” or “MEC”), a leading U.S.-based value-added manufacturing partner that provides a bro

Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 26, 2019 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorpo

Amended and Restated Credit Agreement, dated as of September 26, 2019, by and among Mayville Engineering Company, Inc., the lenders from time to time party thereto, Wells Fargo Bank, National Association, as Administrative Agent for the lenders, and Wells Fargo Securities, LLC, as Sole Lead Arranger and Sole Bookrunner (incorporated by reference to Exhibit 10 to the Company’s Current Report on Form 8-K filed on October 2, 2019).

EX-10 Exhibit 10 Published CUSIP Number: 57859VAM5 $200,000,000.00 AMENDED AND RESTATED CREDIT AGREEMENT dated as of September 26, 2019, by and among MAYVILLE ENGINEERING COMPANY, INC. as Borrower, the Lenders referred to herein, as Lenders, and WELLS FARGO BANK, NATIONAL ASSOCIATION, as Administrative Agent, Swingline Lender and Issuing Lender and WELLS FARGO SECURITIES, LLC, as Sole Lead Arrange

August 9, 2019

10-Q Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2019 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38894 Mayville Engineering Company, Inc.

Financial Statements and Exhibits, Results of Operations and Financial Condition

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 6, 2019 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporati

MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES SECOND QUARTER 2019 RESULTS Robust Operating Results in Line with Internal Expectations; Reaffirming 2019 Outlook

EX-99 Exhibit 99 MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES SECOND QUARTER 2019 RESULTS Robust Operating Results in Line with Internal Expectations; Reaffirming 2019 Outlook Mayville, WI/August 6, 2019/Mayville Engineering Company (NYSE: MEC) (the “Company” or “MEC”), a leading U.S.-based value-added manufacturing partner that provides a broad range of prototyping and tooling, production fabrica

Mayville Engineering Company, Inc. Long-Term Incentive Plan, as amended and restated effective May 13, 2019 (incorporated by reference to Exhibit 10.1 to the Company’s Quarterly Report on Form 10-Q filed on June 18, 2019).

EX-10.1 Exhibit 10.1 MAYVILLE ENGINEERING COMPANY, INC. LONG-TERM INCENTIVE PLAN As Amended and Restated Effective May 13, 2019 Table of Contents Page ARTICLE 1 DEFINITIONS 1 1.1 Affiliate 1 1.2 Award Agreement 1 1.3 Code 1 1.4 Company 1 1.5 Company Value 1 1.6 Compensation Committee 2 1.7 Employer 2 1.8 ESOP 2 1.9 Incentive Compensation Plan 2 1.10 IPO 2 1.11 Participant 2 1.12 Performance Period

March 31, 2019

10-Q Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2019 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38894 Mayville Engineering Company, Inc.

Form of Restricted Stock Unit Award Agreement (Non-Employee Director) under the Mayville Engineering Company, Inc. 2019 Omnibus Incentive Plan (incorporated by reference to Exhibit 10.2 to the Company’s Quarterly Report on Form 10-Q filed on June 18, 2019).

EX-10.2 Exhibit 10.2 MAYVILLE ENGINEERING COMPANY, INC. 2019 OMNIBUS INCENTIVE PLAN RESTRICTED STOCK UNIT AWARD (NON-EMPLOYEE DIRECTOR FORM) [PARTICIPANTID] [FIRSTNAME] [LASTNAME] You have been granted an award of Restricted Stock Units (this “Award”) of Mayville Engineering Company, Inc. (the “Company”) under the Mayville Engineering Company, Inc. 2019 Omnibus Incentive Plan (the “Plan”), effecti

Form of Restricted Stock Unit Award Agreement (Employee) under the Mayville Engineering Company, Inc. 2019 Omnibus Incentive Plan (incorporated by reference to Exhibit 10.3 to the Company’s Quarterly Report on Form 10-Q filed on June 18, 2019).

EX-10.3 Exhibit 10.3 MAYVILLE ENGINEERING COMPANY, INC. 2019 OMNIBUS INCENTIVE PLAN RESTRICTED STOCK UNIT AWARD (EMPLOYEE FORM) [PARTICIPANTID] [FIRSTNAME] [LASTNAME] You have been granted an award of Restricted Stock Units (this “Award”) of Mayville Engineering Company, Inc. (the “Company”) under the Mayville Engineering Company, Inc. 2019 Omnibus Incentive Plan (the “Plan”), effective as of the

Mayville Engineering Company, Inc. Announces Management Promotions

EX-99 Exhibit 99 Mayville Engineering Company, Inc. Announces Management Promotions Mayville, WI — June 12, 2019 — Mayville Engineering Company (NYSE: MEC) (the “Company” or “MEC”), a leading U.S.-based value-added manufacturing partner that provides a broad range of prototyping and tooling, production fabrication, coating, assembly and aftermarket services, today announced two senior management p

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 12, 2019 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporatio

MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES FIRST QUARTER 2019 RESULTS Positive Operating Results and Progress with Integration of DMP Acquisition; Successfully Completed IPO on May 13, 2019

EX-99 Exhibit 99 MAYVILLE ENGINEERING COMPANY, INC. ANNOUNCES FIRST QUARTER 2019 RESULTS Positive Operating Results and Progress with Integration of DMP Acquisition; Successfully Completed IPO on May 13, 2019 Mayville, WI/May 28, 2019/Mayville Engineering Company (NYSE: MEC) (the “Company” or “MEC”), a leading U.S.-based value-added manufacturing partner that provides a broad range of prototyping

Financial Statements and Exhibits, Results of Operations and Financial Condition

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 28, 2019 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorporation

Termination of a Material Definitive Agreement, Financial Statements and Exhibits

Form 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 13, 2019 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 001-38894 39-0944729 (State or other jurisdiction of incorpor

First Amendment to Credit Agreement, effective as of May 12, 2019, by and among Mayville Engineering Company, Inc., the lenders from time to time party thereto, and Wells Fargo Bank, National Association, as Administrative Agent for the lenders.

EX-10.1 Exhibit 10.1 FIRST AMENDMENT TO CREDIT AGREEMENT THIS FIRST AMENDMENT TO CREDIT AGREEMENT is made as of May 7, 2019, to be effective on the First Amendment Effective Date (defined below), by and among MAYVILLE ENGINEERING COMPANY, INC., a Wisconsin corporation (“Borrower”), the lenders party to this Amendment (the “Lenders”), and WELLS FARGO BANK, NATIONAL ASSOCIATION, a national banking a

Operational Footprint

424B4 Table of Contents Filed Pursuant to Rule 424(b)(4) Registration No. 333-230840 PROSPECTUS 6,250,000 Shares MAYVILLE ENGINEERING COMPANY, INC. COMMON STOCK This is the initial public offering of common stock of Mayville Engineering Company, Inc. We are offering 6,250,000 shares of our common stock. Prior to this offering, there has been no public market for our common stock. The initial publi

MEC / Mayville Engineering Company, Inc. CORRESP - -

Acceleration Request MAYVILLE ENGINEERING COMPANY, INC. 715 South Street Mayville, Wisconsin 53050 May 6, 2019 VIA EDGAR Division of Corporation Finance Office of Manufacturing and Construction U.S. Securities and Exchange Commission 100 F Street NE Washington, DC 20549 Attention: Mindy Hooker Kevin Stertzel Sherry Haywood Jay Ingram Re: Mayville Engineering Company, Inc. Registration Statement on

MEC / Mayville Engineering Company, Inc. CORRESP - -

Acceleration Request VIA EDGAR May 6, 2019 Securities and Exchange Commission 100 F Street, N.

As filed with the Securities and Exchange Commission on May 3, 2019.

Table of Contents As filed with the Securities and Exchange Commission on May 3, 2019.

The description of the Common Stock contained in the Company’s Registration Statement on Form 8-A (File No. 001-38894) filed with the Commission on May 3, 2019 pursuant to Section 12(b) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), including any amendment or report filed for the purpose of updating such description.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-A FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES PURSUANT TO SECTION 12(b) OR 12(g) OF THE SECURITIES EXCHANGE ACT OF 1934 Mayville Engineering Company, Inc. (Exact name of registrant as specified in its charter) Wisconsin 39-0944729 (State of incorporation or organization) (I.R.S. Employer Identification No.) 715 So

MEC / Mayville Engineering Company, Inc. CORRESP - -

CORRESP ATTORNEYS AT LAW 777 EAST WISCONSIN AVENUE MILWAUKEE, WI 53202-5306 414.271.2400 TEL 414.297.4900 FAX WWW.FOLEY.COM WRITER’S DIRECT LINE 414.297.5668 [email protected] EMAIL May 3, 2019 Division of Corporation Finance Office of Manufacturing and Construction U.S. Securities and Exchange Commission 100 F Street NE Washington, DC 20549 Attention: Mindy Hooker Kevin Stertzel Sherry Haywood Jay

Form of Underwriting Agreement.

Exhibit 1 [?] Shares MAYVILLE ENGINEERING COMPANY, INC. COMMON STOCK, NO PAR VALUE PER SHARE UNDERWRITING AGREEMENT [?], 2019 [?], 2019 ROBERT W. BAIRD & CO. INCORPORATED CITIGROUP GLOBAL MARKETS INC. JEFFERIES LLC As Representatives of the Several Underwriters Identified in Schedule I Hereto c/o Robert W. Baird & Co. Incorporated 777 East Wisconsin Avenue Milwaukee, Wisconsin 53202 c/o Citigroup

Form of Restricted Stock Unit Award Agreement (Employee) under the Mayville Engineering Company, Inc. 2019 Omnibus Incentive Plan.

Exhibit 10.10 MAYVILLE ENGINEERING COMPANY, INC. 2019 OMNIBUS INCENTIVE PLAN RESTRICTED STOCK UNIT AWARD (EMPLOYEE FORM) [PARTICIPANTID] [FIRSTNAME] [LASTNAME] You have been granted an award of Restricted Stock Units (this ?Award?) of Mayville Engineering Company, Inc. (the ?Company?) under the Mayville Engineering Company, Inc. 2019 Omnibus Incentive Plan (the ?Plan?), effective as of the Grant D

Amended and Restated Articles of Incorporation of Mayville Engineering Company, Inc. (incorporated by reference to Exhibit 3.1 to Amendment No. 1 to the Registration Statement on Form S-1 (File No. 333-230840) filed on April 29, 2019).

Exhibit 3.1 AMENDED AND RESTATED ARTICLES OF INCORPORATION OF MAYVILLE ENGINEERING COMPANY, INC. Pursuant to Section 180.1007 of the Wisconsin Business Corporation Law, Chapter 180 of the Wisconsin Statutes, these amended and restated articles of incorporation of the corporation (the ?Corporation?), which Corporation is organized under Chapter 180 of the Wisconsin Statutes, supersede and take the

Form of Restricted Stock Award Agreement (Employee) under the Mayville Engineering Company, Inc. 2019 Omnibus Incentive Plan (incorporated by reference to Exhibit 10.12 to Amendment No. 1 to the Registration Statement on Form S-1 (File No. 333-230840) filed on April 29, 2019).

Exhibit 10.12 MAYVILLE ENGINEERING COMPANY, INC. 2019 OMNIBUS INCENTIVE PLAN RESTRICTED STOCK AWARD (EMPLOYEE FORM) [PARTICIPANTID] [FIRSTNAME] [LASTNAME] You have been granted an award of Restricted Stock (this ?Award?) of Mayville Engineering Company, Inc. (the ?Company?) under the Mayville Engineering Company, Inc. 2019 Omnibus Incentive Plan (the ?Plan?), effective as of the Grant Date, with t

Form of Restricted Stock Award Agreement (Non-Employee Director) under the Mayville Engineering Company, Inc. 2019 Omnibus Incentive Plan (incorporated by reference to Exhibit 10.11 to Amendment No. 1 to the Registration Statement on Form S-1 (File No. 333-230840) filed on April 29, 2019).

Exhibit 10.11 MAYVILLE ENGINEERING COMPANY, INC. 2019 OMNIBUS INCENTIVE PLAN RESTRICTED STOCK AWARD (NON-EMPLOYEE DIRECTOR FORM) [PARTICIPANTID] [FIRSTNAME] [LASTNAME] You have been granted an award of Restricted Stock (this ?Award?) of Mayville Engineering Company, Inc. (the ?Company?) under the Mayville Engineering Company, Inc. 2019 Omnibus Incentive Plan (the ?Plan?), effective as of the Grant

Mayville Engineering Company, Inc. 2019 Omnibus Incentive Plan (incorporated by reference to Exhibit 10.1 to Amendment No. 1 to the Registration Statement on Form S-1 (File No. 333-230840) filed on April 29, 2019).

Exhibit 10.1 MAYVILLE ENGINEERING COMPANY, INC. 2019 OMNIBUS INCENTIVE PLAN 1. Purposes, History and Effective Date. (a) Purpose. The Mayville Engineering Company, Inc. 2019 Omnibus Incentive Plan (the ?Plan?) has two complementary purposes: (i) to attract and retain outstanding individuals to serve as officers, directors, employees, and consultants, and (ii) to increase shareholder value. The Pla

Form of Stock Option Award Agreement under the Mayville Engineering Company, Inc. 2019 Omnibus Incentive Plan (incorporated by reference to Exhibit 10.8 to Amendment No. 1 to the Registration Statement on Form S-1 (File No. 333-230840) filed on April 29, 2019).

Exhibit 10.8 MAYVILLE ENGINEERING COMPANY, INC. 2019 OMNIBUS INCENTIVE PLAN STOCK OPTION AWARD [PARTICIPANTID] [FIRSTNAME] [LASTNAME] You have been granted an option (your ?Option?) to purchase shares (?Shares?) of Common Stock of Mayville Engineering Company, Inc. (the ?Company?) under the Mayville Engineering Company, Inc. 2019 Omnibus Incentive Plan (the ?Plan?), effective as of the Grant Date,

Form of Restricted Stock Unit Award Agreement (Non-Employee Director) under the Mayville Engineering Company, Inc. 2019 Omnibus Incentive Plan.

Exhibit 10.9 MAYVILLE ENGINEERING COMPANY, INC. 2019 OMNIBUS INCENTIVE PLAN RESTRICTED STOCK UNIT AWARD (NON-EMPLOYEE DIRECTOR FORM) [PARTICIPANTID] [FIRSTNAME] [LASTNAME] You have been granted an award of Restricted Stock Units (this ?Award?) of Mayville Engineering Company, Inc. (the ?Company?) under the Mayville Engineering Company, Inc. 2019 Omnibus Incentive Plan (the ?Plan?), effective as of

As filed with the Securities and Exchange Commission on April 29, 2019.

Table of Contents As filed with the Securities and Exchange Commission on April 29, 2019.

Senior Subordinated Credit Agreement, dated as of December 14, 2018, by and among Mayville Engineering Company, Inc., the lenders from time to time party thereto, and Wells Fargo Strategic Capital Inc., as Administrative Agent for the Lenders.

Exhibit 10.5 THIS AGREEMENT AND THE INDEBTEDNESS EVIDENCED HEREBY ARE SUBORDINATE IN THE MANNER AND TO THE EXTENT SET FORTH IN THAT CERTAIN SUBORDINATION AGREEMENT (AS AMENDED, RESTATED, SUPPLEMENTED OR OTHERWISE MODIFIED FROM TIME TO TIME, THE ?SUBORDINATION AGREEMENT?) DATED AS OF DECEMBER 14, 2018, BY AND AMONG MAYVILLE ENGINEERING COMPANY, INC., A WISCONSIN CORPORATION, WELLS FARGO STRATEGIC C

As filed with the Securities and Exchange Commission on April 12, 2019.

Table of Contents As filed with the Securities and Exchange Commission on April 12, 2019.

Memorandum of Agreement between Mayville Engineering Company, Inc. and Robert D. Kamphuis (incorporated by reference to Exhibit 10.7 to the Registration Statement on Form S-1 (File No. 333-230840) filed on April 12, 2019).

Exhibit 10.7 April 7, 2006 Mr. Robert D. Kamphuis President and CEO Mayville Engineering Company, Inc. 715 South Street Mayville, WI 53050 Dear Bob: This letter will serve as a Memorandum of Agreement between you and MEC regarding your plans to purchase real estate and construct a home in the Mayville area. All of the Board members feel that it is extremely important for you, as President and Chie

Mayville Engineering Company, Inc. Deferred Compensation Plan (incorporated by reference to Exhibit 10.3 to the Registration Statement on Form S-1 (File No. 333-230840) filed on April 12, 2019).

Exhibit 10.3 MAYVILLE ENGINEERING DEFERRED COMPENSATION PLAN As Amended and Restated Effective [IPO Date] Table of Contents Page ARTICLE 1. DEFINITIONS 1 1.1 Account 1 1.2 Affiliate 1 1.3 Annual Incentive Compensation 2 1.4 Base Salary 2 1.5 Beneficiary 2 1.6 Code 2 1.7 Committee 3 1.8 Company 3 1.9 Company Stock 3 1.10 Company Stock Unit 3 1.11 Eligible Employee 3 1.12 Employer 3 1.13 Employer Co

Credit Agreement, dated as of December 14, 2018, by and among Mayville Engineering Company, Inc., the lenders from time to time party thereto, Wells Fargo Bank, National Association, as Administrative Agent for the Lenders, and Wells Fargo Securities, LLC, as Sole Lead Arranger and Sole Bookrunner.

Exhibit 10.4 Published CUSIP Number: 57859VAH6 Revolving Credit CUSIP Number: 57859VAJ2 Term Loan A CUSIP Number: 57859VAK9 Real Estate Term Loan CUSIP Number: 57859VAL7 $185,000,000.00 CREDIT AGREEMENT dated as of December 14, 2018, by and among MAYVILLE ENGINEERING COMPANY, INC. as Borrower, the Lenders referred to herein, as Lenders, and WELLS FARGO BANK, NATIONAL ASSOCIATION, as Administrative

Mayville Engineering Company, Inc. Long-Term Incentive Plan.

Exhibit 10.2 MAYVILLE ENGINEERING COMPANY, INC. LONG-TERM INCENTIVE PLAN As Amended and Restated Effective [IPO Date] Table of Contents Page ARTICLE 1 DEFINITIONS 1 1.1 Affiliate 1 1.2 Award Agreement 1 1.3 Code 1 1.4 Company 1 1.5 Company Value 1 1.6 Compensation Committee 2 1.7 Employer 2 1.8 ESOP 2 1.9 Incentive Compensation Plan 2 1.10 IPO 2 1.11 Participant 2 1.12 Performance Period 2 1.13 Pl

List of Subsidiaries of Mayville Engineering Company, Inc.

Exhibit 21 Subsidiaries of Mayville Engineering Company, Inc. (Wisconsin) Name Domicile Center Manufacturing Holdings, Inc. Delaware Center Manufacturing, Inc. Delaware Center ? Moeller Products LLC Delaware Defiance Metal Products Co. Ohio Defiance Metal Products of Arkansas, Inc. Arkansas Defiance Metal Products of PA., Inc. Pennsylvania Defiance Metal Products of WI, Inc. Wisconsin

MEC / Mayville Engineering Company, Inc. CORRESP - -

CORRESP ATTORNEYS AT LAW 777 EAST WISCONSIN AVENUE MILWAUKEE, WI 53202-5306 414.271.2400 TEL 414.297.4900 FAX WWW.FOLEY.COM WRITER’S DIRECT LINE 414.297.5668 [email protected] EMAIL April 12, 2019 Division of Corporation Finance Office of Manufacturing and Construction U.S. Securities and Exchange Commission 100 F Street NE Washington, DC 20549 Attention: Mindy Hooker Kevin Stertzel Sherry Haywood J

Letter of CliftonLarsonAllen LLP.

EX-16 10 d725632dex16.htm EX-16 Exhibit 16 CLA (CliftonLarsonAllen LLP) 11414 West Park Place, Suite 200 Milwaukee, WI 53224-3500 414-463-4411 | fax 414-577-0343 CLAconnect.com February 7, 2019 Securities and Exchange Commission 100 F. Street, N.E. Washington, D.C. 20549 Commissioners: We have read the section under the heading “Change in Accountants” included in the Registration Statement on Form

Bylaws of the Company (incorporated by reference to Exhibit 3.2 to the Company’s Registration Statement on Form S-1 (Reg. No. 333-230840)).

Exhibit 3.2 BYLAWS OF MAYVILLE ENGINEERING COMPANY, INC. (a Wisconsin corporation) ARTICLE I. OFFICES 1.01 Principal and Business Offices. The corporation may have such principal and other business offices, either within or without the State of Wisconsin, as the Board of Directors may designate or as the business of the corporation may require from time to time. 1.02 Registered Office. The registe

Stock Purchase Agreement, dated December 14, 2018, by and between DMP Acquisition LLC and Mayville Engineering Company, Inc.

Exhibit 2 EXECUTION VERSION STOCK PURCHASE AGREEMENT BY AND BETWEEN DMP ACQUISITION LLC AND MAYVILLE ENGINEERING COMPANY, INC.

Form of Severance Agreement between Mayville Engineering Company, Inc. and each of Robert D. Kamphuis and Todd M. Butz (incorporated by reference to Exhibit 10.6 to the Registration Statement on Form S-1 (File No. 333-230840) filed on April 12, 2019).

Exhibit 10.6 SEVERANCE AGREEMENT THIS SEVERANCE AGREEMENT, effective as of the [ ] day of [ ], 2019 (this ?Agreement?), is by and between MAYVILLE ENGINEERING COMPANY, INC. a Wisconsin corporation (the ?Company?), and [ ] (the ?Executive?). WITNESSETH: WHEREAS, the Executive is currently serving as the Company?s [POSITION]. WHEREAS, in connection with the Company?s initial public offering (the ?IP

Draft No. 2 confidentially submitted to the Securities and Exchange Commission on March 22, 2019. This draft registration statement has not been publicly filed with the Securities and Exchange Commission and all information herein remains strictly co

Table of Contents Draft No. 2 confidentially submitted to the Securities and Exchange Commission on March 22, 2019. This draft registration statement has not been publicly filed with the Securities and Exchange Commission and all information herein remains strictly confidential. Registration No. 333- UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM S-1 REGISTRATION STAT

MEC / Mayville Engineering Company, Inc. DRSLTR - -

DRSLTR ATTORNEYS AT LAW 777 EAST WISCONSIN AVENUE MILWAUKEE, WI 53202-5306 414.271.2400 TEL 414.297.4900 FAX WWW.FOLEY.COM WRITER’S DIRECT LINE 414.297.5668 [email protected] EMAIL March 22, 2019 Division of Corporation Finance Office of Manufacturing and Construction U.S. Securities and Exchange Commission 100 F Street NE Washington, DC 20549 Attention: Mindy Hooker Kevin Stertzel Sherry Haywood Ja

Subsidiaries of Mayville Engineering Company, Inc. (Wisconsin) Name Domicile Center Manufacturing Holdings, Inc. Delaware Center Manufacturing, Inc. Delaware Center – Moeller Products LLC Delaware Defiance Metal Products Co. Ohio Defiance Metal Produ

Exhibit 21 Subsidiaries of Mayville Engineering Company, Inc. (Wisconsin) Name Domicile Center Manufacturing Holdings, Inc. Delaware Center Manufacturing, Inc. Delaware Center ? Moeller Products LLC Delaware Defiance Metal Products Co. Ohio Defiance Metal Products of Arkansas, Inc. Arkansas Defiance Metal Products of PA., Inc. Pennsylvania Defiance Metal Products of WI, Inc. Wisconsin

$25,000,000.00 SENIOR SUBORDINATED CREDIT AGREEMENT dated as of December 14, 2018, by and among MAYVILLE ENGINEERING COMPANY, INC. as Borrower, the Lenders referred to herein, as Lenders, WELLS FARGO STRATEGIC CAPITAL, INC., as Administrative Agent,

Exhibit 10.5 THIS AGREEMENT AND THE INDEBTEDNESS EVIDENCED HEREBY ARE SUBORDINATE IN THE MANNER AND TO THE EXTENT SET FORTH IN THAT CERTAIN SUBORDINATION AGREEMENT (AS AMENDED, RESTATED, SUPPLEMENTED OR OTHERWISE MODIFIED FROM TIME TO TIME, THE ?SUBORDINATION AGREEMENT?) DATED AS OF DECEMBER 14, 2018, BY AND AMONG MAYVILLE ENGINEERING COMPANY, INC., A WISCONSIN CORPORATION, WELLS FARGO STRATEGIC C

STOCK PURCHASE AGREEMENT BY AND BETWEEN DMP ACQUISITION LLC MAYVILLE ENGINEERING COMPANY, INC.

Exhibit 2 EXECUTION VERSION STOCK PURCHASE AGREEMENT BY AND BETWEEN DMP ACQUISITION LLC AND MAYVILLE ENGINEERING COMPANY, INC.

$185,000,000.00 CREDIT AGREEMENT dated as of December 14, 2018, by and among MAYVILLE ENGINEERING COMPANY, INC. as Borrower, the Lenders referred to herein, as Lenders, WELLS FARGO BANK, NATIONAL ASSOCIATION, as Administrative Agent, Swingline Lender

Exhibit 10.4 Published CUSIP Number: 57859VAH6 Revolving Credit CUSIP Number: 57859VAJ2 Term Loan A CUSIP Number: 57859VAK9 Real Estate Term Loan CUSIP Number: 57859VAL7 $185,000,000.00 CREDIT AGREEMENT dated as of December 14, 2018, by and among MAYVILLE ENGINEERING COMPANY, INC. as Borrower, the Lenders referred to herein, as Lenders, and WELLS FARGO BANK, NATIONAL ASSOCIATION, as Administrative

MEC / Mayville Engineering Company, Inc. DRSLTR - -

DRSLTR ATTORNEYS AT LAW 777 EAST WISCONSIN AVENUE MILWAUKEE, WI 53202-5306 414.271.2400 TEL 414.297.4900 FAX WWW.FOLEY.COM WRITER’S DIRECT LINE 414.297.5668 [email protected] EMAIL February 8, 2019 CONFIDENTIAL VIA EDGAR U.S. Securities and Exchange Commission Division of Corporation Finance 100 F Street, N.E. Washington, D.C. 20549 Re: Mayville Engineering Company, Inc. Confidential Submission of t

As confidentially submitted to the Securities and Exchange Commission on February 8, 2019. This draft registration statement has not been publicly filed with the Securities and Exchange Commission and all information herein remains strictly confident

Table of Contents As confidentially submitted to the Securities and Exchange Commission on February 8, 2019.

CLA (CliftonLarsonAllen LLP)

Exhibit 16 CLA (CliftonLarsonAllen LLP) 11414 West Park Place, Suite 200 Milwaukee, WI 53224-3500 414-463-4411 | fax 414-577-0343 CLAconnect.