Mayville Engineering (MEC) CEO sells 21,796 shares under 10b5-1 trading plan

Rhea-AI Filing Summary

Mayville Engineering Company, Inc. President & CEO Jagadeesh A. Reddy reported open-market sales of company stock. On May 7, 2026, he sold 11,464 common shares at a weighted average price of $26.11 and 10,332 shares at a weighted average price of $25.72, totaling 21,796 shares. These transactions were carried out under a pre-arranged Rule 10b5-1 trading plan adopted on December 12, 2025. After the reported sales, one line in the filing shows direct ownership of 158,387 common shares, alongside stock options and restricted stock units that may convert into additional shares over time.

Insights

Equity compensation and insider-trading analyst

CEO executes pre-planned sales while retaining a sizable equity stake.

The President & CEO of Mayville Engineering, Jagadeesh A. Reddy, reported selling a total of 21,796 common shares on May 7, 2026, at weighted average prices of $25.72 and $26.11. The filing states these trades were made under a Rule 10b5-1 trading plan adopted on December 12, 2025, indicating they were pre-scheduled rather than opportunistic.

Following these sales, one transaction line shows direct ownership of 158,387 common shares. The derivative section lists stock options over 88,901 underlying shares at an exercise price of $16.22, plus several tranches of restricted stock units covering 74,986, 55,284, and 36,317 underlying shares. These RSUs vest in thirds on March 15 of successive years through 2029, while the options vest in two installments on February 28, 2024 and February 28, 2025.

The combination of open-market sales and substantial remaining equity exposure suggests routine portfolio management and compensation realization rather than a complete exit. Future company filings can clarify how much of the CEO’s total compensation continues to be delivered in equity and how quickly the remaining options and RSUs are exercised or vest.

Insider Trade Summary 10b5-1

Net Seller: 21,796 shares ($565,064)

Net Sell 8 txns

Insider Reddy Jagadeesh A

Role President & CEO

Sold 21,796 shs ($565K)

Type	Security	Shares	Price	Value
Sale	Common Stock	10,332	$25.72	$266K
Sale	Common Stock	11,464	$26.11	$299K
holding	Restricted Stock Units	--	--	--
holding	Restricted Stock Units	--	--	--
holding	Restricted Stock Units	--	--	--
holding	Stock Option (right to buy)	--	--	--
holding	Common Stock	--	--	--
holding	Common Stock	--	--	--

Holdings After Transaction: Common Stock — 169,851 shares (Direct, null); Restricted Stock Units — 36,317 shares (Direct, null); Stock Option (right to buy) — 88,901 shares (Direct, null); Common Stock — 2,300 shares (Indirect, by ESOP and/or 401(k) Plan)

Footnotes (1)

1. The reported transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 12, 2025. The price in Column 4 is a weighted average price. The prices actually received ranged from $25.00 to $25.99. The reporting person has provided to the issuer, and will provide to any security holder of the issuer, or the SEC staff, upon request, information regarding the number of shares sold at each price within the range for all transactions reported in this Form 4 utilizing a weighted average price. The price in Column 4 is a weighted average price. The prices actually received ranged from $26.00 to $26.28. The reporting person has provided to the issuer, and will provide to any security holder of the issuer, or the SEC staff, upon request, information regarding the number of shares sold at each price within the range for all transactions reported in this Form 4 utilizing a weighted average price. Reflects the most recent ESOP and 401(k) balance. The restricted stock units will vest 1/3 on each of March 15, 2025, 2026 and 2027. The restricted stock units will vest 1/3 on each of March 15, 2026, 2027 and 2028. The restricted stock units will vest 1/3 on each of March 15, 2027, 2028 and 2029. The options will vest 50% on each of February 28, 2024 and February 28, 2025.

Key Figures

Shares sold: 21,796 shares Sale price 1: $26.11 per share Sale price 2: $25.72 per share +5 more

8 metrics

Shares sold 21,796 shares Total common shares sold on May 7, 2026

Sale price 1 $26.11 per share Weighted average price for 11,464-share sale

Sale price 2 $25.72 per share Weighted average price for 10,332-share sale

Direct common shares 158,387 shares Direct common stock shown after a reported sale

Stock option underlying shares 88,901 shares Underlying common shares at $16.22 exercise price

RSU tranche 1 74,986 shares Underlying common shares for one RSU award

RSU tranche 2 55,284 shares Underlying common shares for second RSU award

RSU tranche 3 36,317 shares Underlying common shares for third RSU award

Key Terms

Rule 10b5-1 trading plan, Restricted Stock Units, Stock Option (right to buy), weighted average price, +1 more

5 terms

Rule 10b5-1 trading plan regulatory

"The reported transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 12, 2025."

A Rule 10b5-1 trading plan is a pre-arranged schedule that allows company insiders to buy or sell stock at specific times, even if they have inside information. It helps prevent accusations of unfair trading by making these transactions look planned and transparent, rather than sneaky or illegal.

Restricted Stock Units financial

"The restricted stock units will vest 1/3 on each of March 15, 2025, 2026 and 2027."

Restricted stock units are a type of company reward where employees are promised shares of stock, but they only fully own these shares after meeting certain conditions, like staying with the company for a set time. They matter because they can become valuable assets and are often used to motivate employees to help the company succeed.

Stock Option (right to buy) financial

"Stock Option (right to buy) ... underlying security title Common Shares"

weighted average price financial

"The price in Column 4 is a weighted average price."

Weighted average price is the average price of a security where each trade or component is counted according to its size, so bigger trades pull the average more than smaller ones. Think of it like calculating the average cost of a grocery haul where items you bought more of have greater influence on the final per-item cost. Investors use it to understand the true average price paid or received, judge execution quality, and compare trading performance against market movement.

ESOP and 401(k) Plan financial

"Reflects the most recent ESOP and 401(k) balance."

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

X

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Reddy Jagadeesh A

(Last) (First) (Middle)

135 SOUTH 84TH STREET

SUITE 300

(Street)

MILWAUKEE WISCONSIN 53214

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
Mayville Engineering Company, Inc. [ MEC ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	President & CEO

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/07/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	05/07/2026		S(1)		10,332	D	$25.72(2)	169,851	D
Common Stock	05/07/2026		S(1)		11,464	D	$26.11(3)	158,387	D
Common Stock								2,300(4)	I	by ESOP and/or 401(k) Plan
Common Stock								380	I	By Daughter

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Restricted Stock Units	$0							(5)	(5)	Common Shares	36,317		36,317	D
Restricted Stock Units	$0							(6)	(6)	Common Shares	55,284		55,284	D
Restricted Stock Units	$0							(7)	(7)	Common Shares	74,986		74,986	D
Stock Option (right to buy)	$16.22							(8)	(8)	Common Shares	88,901		88,901	D

Explanation of Responses:

1. The reported transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 12, 2025.

2. The price in Column 4 is a weighted average price. The prices actually received ranged from $25.00 to $25.99. The reporting person has provided to the issuer, and will provide to any security holder of the issuer, or the SEC staff, upon request, information regarding the number of shares sold at each price within the range for all transactions reported in this Form 4 utilizing a weighted average price.

3. The price in Column 4 is a weighted average price. The prices actually received ranged from $26.00 to $26.28. The reporting person has provided to the issuer, and will provide to any security holder of the issuer, or the SEC staff, upon request, information regarding the number of shares sold at each price within the range for all transactions reported in this Form 4 utilizing a weighted average price.

4. Reflects the most recent ESOP and 401(k) balance.

5. The restricted stock units will vest 1/3 on each of March 15, 2025, 2026 and 2027.

6. The restricted stock units will vest 1/3 on each of March 15, 2026, 2027 and 2028.

7. The restricted stock units will vest 1/3 on each of March 15, 2027, 2028 and 2029.

8. The options will vest 50% on each of February 28, 2024 and February 28, 2025.

	/s/ Garrett F. Bishop, Attorney-in-Fact for Jagadeesh A. Reddy	05/11/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)

FAQ

How many Mayville Engineering (MEC) shares did the CEO sell in this Form 4?

The President & CEO sold a total of 21,796 common shares. The filing shows two open-market sales on May 7, 2026, of 11,464 shares at $26.11 and 10,332 shares at $25.72 weighted average prices.

At what prices did Mayville Engineering (MEC) shares trade in the CEO’s reported sales?

The reported weighted average prices were $26.11 and $25.72 per share. Footnotes explain actual prices ranged from $25.00–$25.99 and $26.00–$26.28, with detailed breakdowns available from the issuer or the CEO upon request.

Were the Mayville Engineering (MEC) CEO stock sales made under a Rule 10b5-1 plan?

Yes. A footnote states the reported transactions were effected under a Rule 10b5-1 trading plan. That plan was adopted by the CEO on December 12, 2025, indicating the sales were pre-arranged rather than timed after new information.

How many Mayville Engineering (MEC) shares does the CEO hold after these sales?

One transaction line shows direct ownership of 158,387 common shares after a reported sale. In addition, the filing lists stock options and restricted stock units that, if exercised or vested, are tied to substantial additional underlying common shares.

What stock options does the Mayville Engineering (MEC) CEO have outstanding?

The filing lists a stock option over 88,901 underlying common shares with an exercise price of $16.22. According to the footnotes, these options vest in two equal installments on February 28, 2024 and February 28, 2025.

What restricted stock units (RSUs) are reported for the Mayville Engineering (MEC) CEO?

Three RSU awards are shown, tied to 74,986, 55,284, and 36,317 underlying common shares. Footnotes state they vest in equal thirds on March 15 of successive years from 2025–2027, 2026–2028, and 2027–2029, respectively.