Eos Energy’s Michelle Buczkowski sells 50,000 shares

The Chief Commercial Officer’s share sale was made under a plan adopted to cover estimated tax withholding tied to RSU vesting.

Available on EDGAR 10/29/2026 - 04:49 PM EDT Accepted by SEC EDGAR 10/29/2026 - 04:49 PM EDT Learn about SEC filing dates

Rhea-AI Filing Summary

Eos Energy Enterprises, Inc. (EOSE) Chief Commercial Officer Michelle Buczkowski reported converting 100,000 restricted stock units into 100,000 common shares on October 28, 2026; the derivative entry lists 100,000 RSUs following the transaction. A footnote describes the RSUs as a grant under the 2020 Incentive Plan, scheduled to vest in three installments on the first three anniversaries of the grant date, subject to continued service.

On October 29, 2026, Buczkowski sold 50,000 common shares at a weighted average price of $2.00 per share, with sale prices ranging from $1.88 to $2.07. The sales were effected automatically under a Rule 10b5-1 plan adopted December 11, 2025, to cover estimated tax withholding obligations in connection with RSU vesting.

Insider Trade Summary 10b5-1

Exercise and sale activity reported; no spread calculated

Exercise and Sale 3 txns

Insider Buczkowski Michelle

Role Chief Commercial Officer

Sold 50,000 shs ($100K)

Approx. gross sale proceeds $100K

Type	Security	Shares	Price	Value
Sale	Common Stock F2, F3	50,000	$2.00	$100K
Exercise	Restricted Stock Units F4, F1, F5	100,000	$0.00	$0.00
Exercise	Common Stock F1	100,000	$0.00	$0.00

Holdings After Transaction: Restricted Stock Units — 100,000 contracts (Direct); Common Stock — 111,827 shares (Direct)

Footnotes (5)

1. F1. Each restricted stock unit ("RSU") represents a contingent right to receive one share of common stock.
2. F2. The sales reported in this Form 4 were effected automatically pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 11, 2025 to cover estimated tax withholding obligations in connection with the vesting of restricted stock units.
3. F3. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $1.88 to $2.07, 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. F4. The reporting person received a grant of RSUs under the Issuer's 2020 Incentive Plan, which will vest in three installments on each of the first three anniversaries of the grant date, subject to continued service through each vesting date.
5. F5. Not applicable.

Key Figures

RSUs converted: 100,000 RSUs Common shares acquired on conversion: 100,000 shares RSUs following transaction: 100,000 RSUs +3 more

6 metrics

RSUs converted 100,000 RSUs October 28, 2026

Common shares acquired on conversion 100,000 shares October 28, 2026

RSUs following transaction 100,000 RSUs As reported in the derivative entry for October 28, 2026

Common shares sold 50,000 shares October 29, 2026

Weighted average sale price $2.00 per share Sale prices ranged from $1.88 to $2.07 per share

Rule 10b5-1 plan adoption date December 11, 2025 Plan for the reported sales

Key Terms

restricted stock unit, Rule 10b5-1 trading plan, weighted average price

3 terms

restricted stock unit financial

"Each restricted stock unit ("RSU") represents a contingent right"

A restricted stock unit is a promise from a company to give an employee shares of stock after certain conditions are met, like staying with the company for a set amount of time. It’s like earning a bonus that turns into company stock once you’ve proven your commitment, making it a way to motivate and reward employees.

Rule 10b5-1 trading plan regulatory

"automatically pursuant to a Rule 10b5-1 trading plan"

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.

weighted average price financial

"The price reported 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.

FAQ

AI-generated questions and answers. How Rhea-AI works. Not financial advice.

How many EOSE shares did Chief Commercial Officer Michelle Buczkowski sell, and at what price?

Michelle Buczkowski sold 50,000 EOSE common shares on October 29, 2026, at a weighted average of $2.00 per share. The sales were made automatically under a Rule 10b5-1 trading plan adopted December 11, 2025, to cover estimated tax withholding obligations related to RSU vesting; prices ranged from $1.88 to $2.07.

What RSU transaction did Michelle Buczkowski report for EOSE?

On October 28, 2026, Buczkowski reported conversion of 100,000 RSUs into 100,000 common shares; the derivative entry reports 100,000 RSUs following the transaction. A footnote describes the RSU grant under the 2020 Incentive Plan as vesting in three installments on the first three anniversaries of the grant date, subject to continued service.

AI-generated analysis. How Rhea-AI works. Not financial advice.

Form 4 Insider Transactions: What Each Field Means →

See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google

Add on Google Not now

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^*

Buczkowski Michelle

(Last) (First) (Middle)

C/O EOS ENERGY ENTERPRISES, INC.

TWO ALLEGHENY CENTER, NOVA TOWER 2

(Street)

PITTSBURGH PENNSYLVANIA 15212

(City) (State) (Zip)

UNITED STATES

(Country)

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

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

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

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
10/28/2026

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	10/28/2026		M		100,000	A	$0(1)	161,827	D
Common Stock	10/29/2026		S(2)		50,000	D	$2(3)	111,827	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)	10/28/2026		M			100,000	(5)	(5)	Common Stock	100,000	$0	100,000	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 December 11, 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 $1.88 to $2.07, 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 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/ Sumeet Puri as attorney-in-fact for Michelle Buczkowski	10/29/2026
	** 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)