Apellis officer sells 368 shares for tax withholding

Apellis Pharmaceuticals Chief Business & Strat Officer Mark DeLong reported a small stock sale mainly for tax purposes.

Rhea-AI Filing Summary

Apellis Pharmaceuticals Chief Business & Strat Officer Mark DeLong reported a small stock sale mainly for tax purposes. On February 11, 2026, he sold 368 shares of Apellis common stock at $22.1537 per share to cover tax withholding tied to Restricted Stock Units released on February 10, 2026. After this transaction, he directly owned 114,591 shares of Apellis common stock.

Insider Trade Summary

Net Seller: 368 shares

Net Sell 1 txn

Insider DeLong Mark Jeffrey

Role Chief Business & Strat Officer

Sold 368 shs ($8K)

Type	Security	Shares	Price	Value
Sale	Common Stock	368	$22.1537	$8K

Holdings After Transaction: Common Stock — 114,591 shares (Direct)

Footnotes (1)

1. F1. This represents shares sold to cover tax withholding on the Restricted Stock Units released on February 10, 2026.

FAQ

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

What insider transaction did Apellis Pharmaceuticals (APLS) report for Mark DeLong?

Apellis Pharmaceuticals reported that Chief Business & Strat Officer Mark DeLong sold 368 shares of common stock on February 11, 2026. The sale was an open-market transaction primarily to cover tax withholding on recently released Restricted Stock Units.

How many Apellis (APLS) shares did Mark DeLong sell and at what price?

Mark DeLong sold 368 shares of Apellis common stock at $22.1537 per share. This open-market sale was disclosed as part of a Form 4 filing and was linked to tax withholding obligations on Restricted Stock Units released the prior day.

Why did Apellis officer Mark DeLong sell shares according to the Form 4?

The Form 4 states the shares were sold to cover tax withholding on Restricted Stock Units released on February 10, 2026. This type of sale is often administrative, helping the insider satisfy tax liabilities triggered by equity awards vesting.

How many Apellis (APLS) shares does Mark DeLong own after the reported sale?

Following the February 11, 2026 transaction, Mark DeLong beneficially owned 114,591 shares of Apellis common stock directly. This figure reflects his holdings after selling 368 shares to address tax withholding tied to recently released Restricted Stock Units.

Was Mark DeLong’s Apellis stock transaction a buy or a sell?

The reported transaction was a sale of Apellis common stock. The Form 4 labels it with transaction code “S,” indicating an open-market or private sale, and notes it was executed to cover tax withholding on vested Restricted Stock Units.

What role does Mark DeLong hold at Apellis Pharmaceuticals (APLS)?

Mark DeLong serves as Chief Business & Strat Officer at Apellis Pharmaceuticals. His position is disclosed in the Form 4, which reports his February 11, 2026 sale of 368 shares and his resulting direct ownership of 114,591 shares of common stock.

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Form 4 Insider Transactions: What Each Field Means →

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Accepted by SEC EDGAR 02/13/2026 - 09:23 AM EST Learn about SEC filing dates

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^*

DeLong Mark Jeffrey

(Last) (First) (Middle)

C/O APELLIS PHARMACEUTICALS, INC.

100 FIFTH AVENUE, 3RD FLOOR

(Street)

WALTHAM MA 02451

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Apellis Pharmaceuticals, Inc. [ APLS ]

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

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Business & Strat Officer

3. Date of Earliest Transaction (Month/Day/Year)
02/11/2026

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	02/11/2026		S(1)		368	D	$22.1537	114,591	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. This represents shares sold to cover tax withholding on the Restricted Stock Units released on February 10, 2026.

	/s/ David Watson, attorney-in-fact for Mark DeLong	02/13/2026
	** 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.