Director at Mercury Systems (NASDAQ: MRCY) granted 245 DSUs

Rhea-AI Filing Summary

Mercury Systems Inc director Barry R. Nearhos received a grant of 245 deferred stock units in lieu of a quarterly cash retainer for his board service. These units were fully vested on grant but will not convert into common stock until he leaves the Board of Directors. Following this award, he holds 31,324 deferred stock units directly and has an additional 3,500 shares reported as indirectly owned through his spouse.

Insider Trade Summary

2 transactions reported

Mixed 2 txns

Insider Nearhos Barry R

Role Director

Type	Security	Shares	Price	Value
Grant/Award	Common Stock	245	$0.00	--
holding	Common Stock	--	--	--

Holdings After Transaction: Common Stock — 31,324 shares (Direct); Common Stock — 3,500 shares (Indirect, By Spouse)

Footnotes (1)

1. [object Object]

Key Figures

Deferred stock units granted: 245 units Direct deferred stock units after grant: 31,324 units Indirectly owned common shares: 3,500 shares

3 metrics

Deferred stock units granted 245 units Quarterly cash retainer replacement for director service

Direct deferred stock units after grant 31,324 units Held by director Barry R. Nearhos following the April 16, 2026 grant

Indirectly owned common shares 3,500 shares Reported as owned indirectly by spouse

Key Terms

deferred stock units (DSUs), quarterly cash retainer, fully vested upon grant, Board of Directors

4 terms

deferred stock units (DSUs) financial

"Represents deferred stock units (DSUs) issued in lieu of a quarterly cash retainer payment"

Deferred stock units (DSUs) are a form of long-term pay that promises an employee or director future company shares or cash equal to the share value at a later date, usually after leaving the company or at a set vesting time. Think of them as a delayed paycheck tied to the stock: they align recipients’ interests with long-term share performance and matter to investors because they create potential future dilution and signal how management is rewarded and incentivized.

quarterly cash retainer financial

"issued in lieu of a quarterly cash retainer payment for service as a director"

fully vested upon grant financial

"These DSUs were fully vested upon grant, but do not convert into shares"

Board of Directors financial

"until the date on which the reporting person ceases to be a member of our Board of Directors"

The Board of Directors is a group of people chosen by a company's owners to help make big decisions and oversee how the company is run. They act like a team of advisors or managers, making sure the company stays on track and meets its goals. Their choices can influence the company's success and how it grows.

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).

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^*

Nearhos Barry R

(Last) (First) (Middle)

50 MINUTEMAN ROAD

(Street)

ANDOVER MASSACHUSETTS 01810

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
MERCURY SYSTEMS INC [ MRCY ]

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

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

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
04/16/2026

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	04/16/2026		A		245(1)	A	$0	31,324	D
Common Stock								3,500	I	By Spouse

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

Explanation of Responses:

1. Represents deferred stock units (DSUs) issued in lieu of a quarterly cash retainer payment for service as a director. These DSUs were fully vested upon grant, but do not convert into shares of common stock until the date on which the reporting person ceases to be a member of our Board of Directors.

	/s/ Douglas Munro, attorney-in-fact	04/17/2026
	** 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

What insider transaction did Mercury Systems (MRCY) report for Barry R. Nearhos?

Mercury Systems reported that director Barry R. Nearhos received 245 deferred stock units. The units were granted as compensation in lieu of a quarterly cash retainer for board service and were fully vested upon grant but settle in common stock only when he leaves the board.

How many Mercury Systems (MRCY) deferred stock units does Barry R. Nearhos now hold?

After the latest grant, Barry R. Nearhos holds 31,324 deferred stock units directly. These units are fully vested but will not convert into shares of common stock until he ceases to be a member of the Mercury Systems Board of Directors.

Are the new Mercury Systems (MRCY) stock units for Barry R. Nearhos immediately tradeable?

The 245 deferred stock units granted to Barry R. Nearhos are not immediately tradeable as common stock. They are fully vested but will convert into shares of Mercury Systems common stock only when he is no longer serving on the Board of Directors.

How are Barry R. Nearhos’s Mercury Systems (MRCY) indirect holdings reported?

In addition to his direct deferred stock units, 3,500 shares of Mercury Systems common stock are reported as indirectly owned by Barry R. Nearhos through his spouse. This reflects family-related ownership and is disclosed separately from his direct deferred stock unit holdings.

What is the purpose of the deferred stock units granted to Mercury Systems (MRCY) directors?

The deferred stock units granted to Mercury Systems directors, such as the 245 units for Barry R. Nearhos, are issued instead of a quarterly cash retainer. They provide equity-based compensation that vests immediately but settles in common stock only after the director leaves the board.