[Form 4] Eos Energy Enterprises, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Eos Energy Enterprises (EOSE) Form 4 details CEO and Director Joe Mastrangelo’s insider transactions.

• 07/25/25: 333,333 restricted stock units (RSUs) vested and were converted to common shares (Code M) at $0 cost.
• 07/29/25: 166,667 shares sold (Code S) under a pre-arranged Rule 10b5-1 plan at a weighted-avg $5.94 (range $5.80-$6.29) to cover tax obligations.

Post-transaction ownership: 1,403,226 common shares held directly and 666,667 unvested RSUs that vest in equal installments on the next two anniversaries of the grant date. The sale equals ~12% of the newly issued shares and leaves the CEO with significant equity exposure.

No operational or financial metrics were included; the filing strictly reports insider trading activity.

Positive

• CEO retains 1.4 m shares and 0.67 m RSUs, indicating sustained alignment with shareholders.
• Sale executed under a Rule 10b5-1 plan, enhancing governance transparency.

Negative

• Insider sale of 166,667 shares could be viewed as a modest sentiment drag despite tax-related rationale.

Insights

Financial Analyst

TL;DR: Neutral—routine RSU vesting; limited sell for taxes, CEO retains large stake.

The conversion of RSUs into 333k shares is a standard compensation event. The follow-on sale of 166.7k shares (~$0.99 m) was executed under a 10b5-1 plan, signalling pre-planned liquidity rather than opportunistic selling. Mastrangelo still controls 1.4 m shares plus 0.67 m RSUs, maintaining meaningful alignment with shareholders. Market impact should be minimal given modest volume and clear purpose of sale.

Corporate Governance Expert

TL;DR: Governance sound; transparent 10b5-1 use mitigates insider-sale concerns.

Filing shows compliance with SEC disclosure and the company’s 2020 Incentive Plan. The preset trading plan and prompt reporting reduce litigation and perception risk. Continued unvested RSUs incentivise long-term performance. No red flags on control or significant dilution were observed.

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

1. Name and Address of Reporting Person^*

Mastrangelo Joe

(Last) (First) (Middle)

C/O EOS ENERGY ENTERPRISES, INC.

3920 PARK AVENUE

(Street)

EDISON NJ 08820

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Eos Energy Enterprises, Inc. [ EOSE ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
07/25/2025

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

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

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

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	07/25/2025		M		333,333	A	$0(1)	1,569,893	D
Common Stock	07/29/2025		S(2)		166,667	D	$5.94(3)	1,403,226	D

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(4)	(1)	07/25/2025		M			333,333	(5)	(5)	Common Stock	333,333	$0	666,667	D

Explanation of Responses:

1. Each restricted stock unit ("RSU") represents a contingent right to receive one share of common stock.

2. The sales reported in this Form 4 were effected automatically pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 14, 2025 to cover estimated tax withholding obligations in connection with the vesting of restricted stock units.

3. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $5.80 to $6.29, inclusive. The reporting person undertakes to provide the issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above.

4. The reporting person received a grant of RSUs under the Issuer's 2020 Incentive Plan, which will vest in three equal installments on each of the first three anniversaries of the grant date, subject to continued service through each vesting date.

5. Not applicable.

Remarks:

	/s/ Michael Silberman as attorney-in-fact for Joe Mastrangelo	07/29/2025
	** 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.
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FAQ

How many EOSE shares did the CEO acquire on 07/25/25?

He received 333,333 common shares through RSU vesting.

What price were EOSE shares sold at on 07/29/25?

Shares were sold at a weighted-average price of $5.94, with individual trades between $5.80 and $6.29.

How many EOSE shares does Joe Mastrangelo now own?

After the transactions he directly owns 1,403,226 shares.

Why did the CEO sell EOSE stock?

Sales were automatic under a Rule 10b5-1 plan to cover estimated tax withholding from RSU vesting.

How many unvested RSUs remain with the CEO?

He retains 666,667 unvested RSUs scheduled to vest in two equal future tranches.