Solid Power (SLDP) CFO has 136,122 shares withheld for RSU taxes

Rhea-AI Filing Summary

Solid Power, Inc. reported that CFO, Treasurer, & Secretary Linda C. Heller had 136,122 shares of common stock withheld on May 11, 2026 to cover tax obligations arising from the vesting of restricted stock units. After this tax-withholding disposition, she directly holds 2,021,154 shares of common stock.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider Heller Linda C.

Role CFO, Treasurer, & Secretary

Type	Security	Shares	Price	Value
Tax Withholding	Common Stock	136,122	$3.075	$419K

Holdings After Transaction: Common Stock — 2,021,154 shares (Direct, null)

Footnotes (1)

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Key Figures

Shares withheld for taxes: 136,122 shares Price per share reference: $3.075 per share Shares held after transaction: 2,021,154 shares

3 metrics

Shares withheld for taxes 136,122 shares Tax-withholding disposition for RSU vesting on May 11, 2026

Price per share reference $3.075 per share Value used for the tax-withholding disposition

Shares held after transaction 2,021,154 shares Direct ownership after tax-withholding disposition

Key Terms

restricted stock units, tax-withholding disposition, Common Stock, Form 4

4 terms

restricted stock units financial

"tax obligation upon the vesting of restricted stock units"

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.

tax-withholding disposition financial

"transaction_action": "tax-withholding disposition""

A tax-withholding disposition is an event or transaction—such as selling or transferring securities, exercising options, or receiving compensation—that triggers a requirement to hold back part of the payment and remit it to tax authorities. It matters to investors because it reduces the cash they receive immediately and can change the timing and amount of taxable income, like a cashier taking a portion of your sale proceeds to pay taxes before you get the rest.

Common Stock financial

""security_title": "Common Stock""

Common stock represents ownership shares in a company, giving investors a stake in its success and a say in important decisions through voting rights. It is the most common type of stock traded on markets and can provide income through dividends, as well as potential for value growth. For investors, holding common stock means sharing in the company’s profits and risks.

Form 4 regulatory

"INSIDER FILING DATA (Form 4)"

Form 4 is a official document that company insiders, such as executives or major shareholders, file with regulators whenever they buy or sell company shares. It provides transparency about how those with inside knowledge are trading, helping investors see if insiders are confident in the company's prospects or may be selling for personal reasons. This information can influence investor decisions by revealing insiders' perspectives on the company's value.

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^*

Heller Linda C.

(Last) (First) (Middle)

486 S. PIERCE AVE.

SUITE E

(Street)

LOUISVILLE COLORADO 80027

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
Solid Power, Inc. [ SLDP ]

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

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	CFO, Treasurer, & Secretary

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/11/2026

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	05/11/2026		F		136,122(1)	D	$3.075	2,021,154	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

Explanation of Responses:

1. Represents shares of the issuer's common stock withheld to satisfy the reporting person's tax obligation upon the vesting of restricted stock units.

	/s/ Kristen Gould, attorney-in-fact on behalf of Linda C. Heller	05/12/2026
	** 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 did Solid Power (SLDP) CFO Linda Heller report in this Form 4?

Linda Heller reported a tax-withholding disposition of 136,122 Solid Power common shares. The shares were withheld to satisfy taxes due on vesting restricted stock units, and she continues to directly hold 2,021,154 common shares afterward.

Was the Solid Power (SLDP) CFO’s Form 4 transaction an open-market stock sale?

No, the transaction was not an open-market sale. The 136,122 shares of Solid Power common stock were withheld by the issuer to cover Linda Heller’s tax obligation upon vesting of restricted stock units, rather than sold on the market.

How many Solid Power (SLDP) shares were withheld for the CFO’s taxes?

A total of 136,122 Solid Power common shares were withheld. The Form 4 identifies this as a tax-withholding disposition, used to satisfy Linda Heller’s tax liability when her restricted stock units vested.

What is Linda Heller’s Solid Power (SLDP) shareholding after this Form 4 event?

Following the tax-withholding disposition, Linda Heller directly holds 2,021,154 shares of Solid Power common stock. This post-transaction balance is reported in the Form 4 as her direct ownership position after the RSU-related tax withholding.

What does transaction code F mean in the Solid Power (SLDP) Form 4?

Transaction code F indicates payment of a tax liability or exercise price by delivering securities. In this case, 136,122 Solid Power common shares were withheld to satisfy Linda Heller’s tax obligation when her restricted stock units vested.