Solid Power (SLDP) CFO granted stock award as shares withheld for taxes

Rhea-AI Filing Summary

Solid Power, Inc. CFO Linda C. Heller received a stock award and had shares withheld for taxes. She was granted 380,348 shares of common stock on April 1, 2026 as a compensation award priced at $0.00 per share, increasing her direct holdings to 2,157,276 shares.

The grant represents restricted stock units that vest in 16 equal quarterly installments starting June 30, 2026, contingent on her continued service. On March 31, 2026, 26,659 shares were withheld at $2.82 per share to cover tax obligations upon RSU vesting, a non-market, tax-related disposition.

Insider Trade Summary

2 transactions reported

Mixed 2 txns

Insider Heller Linda C.

Role CFO, Treasurer, & Secretary

Type	Security	Shares	Price	Value
Grant/Award	Common Stock	380,348	$0.00	--
Tax Withholding	Common Stock	26,659	$2.82	$75K

Holdings After Transaction: Common Stock — 2,157,276 shares (Direct)

Footnotes (1)

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. Each restricted stock unit represents a contingent right to receive one share of the underlying common stock of the Issuer. The restricted stock units will vest in 16 equal quarterly installments commencing on June 30, 2026, and thereafter at the end of each fiscal quarter of the Issuer, subject to the reporting person continuing to be a service provider (as defined in the Solid Power, Inc. 2021 Equity Incentive Plan) through the applicable vesting date.

Key Figures

Equity grant: 380,348 shares Tax withholding shares: 26,659 shares Holdings after transactions: 2,157,276 shares +2 more

5 metrics

Equity grant 380,348 shares Common stock award on April 1, 2026 at $0.00 per share

Tax withholding shares 26,659 shares Shares withheld on March 31, 2026 at $2.82 per share

Holdings after transactions 2,157,276 shares Total common shares directly owned after April 1, 2026 grant

Vesting schedule 16 quarterly installments RSUs vest in equal installments starting June 30, 2026

Tax-withholding value $2.82/share Per-share value used for tax-withholding disposition on March 31, 2026

Key Terms

restricted stock units, tax obligation, 2021 Equity Incentive Plan, vesting

4 terms

restricted stock units financial

"Each restricted stock unit represents a contingent right to receive one share"

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 obligation financial

"withheld to satisfy the reporting person's tax obligation upon the vesting"

2021 Equity Incentive Plan financial

"as defined in the Solid Power, Inc. 2021 Equity Incentive Plan"

vesting financial

"will vest in 16 equal quarterly installments commencing on June 30, 2026"

Vesting is the process by which you earn full ownership of something, like company stock or a retirement benefit, over time. It’s like earning the right to keep a gift piece by piece the longer you stay with a company, making sure employees stay committed before they receive all the benefits.

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)
03/31/2026

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	03/31/2026		F		26,659(1)	D	$2.82	1,776,928	D
Common Stock	04/01/2026		A		380,348(2)	A	$0	2,157,276	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.

2. Each restricted stock unit represents a contingent right to receive one share of the underlying common stock of the Issuer. The restricted stock units will vest in 16 equal quarterly installments commencing on June 30, 2026, and thereafter at the end of each fiscal quarter of the Issuer, subject to the reporting person continuing to be a service provider (as defined in the Solid Power, Inc. 2021 Equity Incentive Plan) through the applicable vesting date.

	/s/ Kristen Gould, attorney-in-fact on behalf of Linda C. Heller	04/02/2026
	** 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) disclose about CFO Linda Heller’s recent equity award?

Solid Power reported that CFO Linda C. Heller received a grant of 380,348 shares of common stock as a stock-based award. These shares stem from restricted stock units that vest over time, aligning her compensation with company performance and tenure.

How do Linda Heller’s new restricted stock units at Solid Power (SLDP) vest?

Each restricted stock unit converts into one Solid Power common share. The 380,348 units vest in 16 equal quarterly installments beginning June 30, 2026. Continued service with the company through each vesting date is required for the shares to be delivered.

Why were 26,659 Solid Power (SLDP) shares disposed of in Linda Heller’s Form 4?

The 26,659 Solid Power shares were withheld to satisfy Linda Heller’s tax obligations when restricted stock units vested. This tax-withholding disposition, at $2.82 per share, is a routine mechanism and not an open-market sale or discretionary stock trade.

How many Solid Power (SLDP) shares does CFO Linda Heller hold after these transactions?

After the reported transactions, Linda Heller directly owns 2,157,276 shares of Solid Power common stock. This figure reflects the addition from the 380,348-share grant and the reduction from 26,659 shares withheld to cover associated tax liabilities.

Are Linda Heller’s recent Solid Power (SLDP) Form 4 transactions open-market buys or sells?

No, the filing shows compensation-related activity, not open-market trading. She received 380,348 shares as a stock award at no cost and had 26,659 shares withheld to cover taxes on vesting, a standard non-market tax-withholding transaction.