Apellis officer sells 1,780 shares for tax withholding

Apellis Pharmaceuticals, Inc. (APLS) reported an insider tax-related share sale by its Chief Business & Strat Officer, Mark DeLong.

Rhea-AI Filing Summary

Apellis Pharmaceuticals, Inc. (APLS) reported an insider tax-related share sale by its Chief Business & Strat Officer, Mark DeLong. On January 13, 2026, DeLong sold 1,780 shares of Apellis common stock at a price of $22.1872 per share. According to the footnotes, these shares were sold solely to cover tax withholding on Restricted Stock Units that were released on January 12, 2026. Following this transaction, DeLong beneficially owned 83,058 shares of Apellis common stock, which includes 893 shares acquired through the company’s employee stock purchase plan on April 30, 2025.

Insider Trade Summary

Net Seller: 1,780 shares

Net Sell 1 txn

Insider DeLong Mark Jeffrey

Role Chief Business & Strat Officer

Sold 1,780 shs ($39K)

Type	Security	Shares	Price	Value
Sale	Common Stock	1,780	$22.1872	$39K

Holdings After Transaction: Common Stock — 83,058 shares (Direct)

Footnotes (2)

1. F1. This represents shares sold to cover tax withholding on the Restricted Stock Units released on January 12, 2026.
2. F2. This includes 893 shares from April 30, 2025 ESPP purchase.

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 1,780 shares of Apellis common stock on January 13, 2026.

At what price were the Apellis (APLS) shares sold in this Form 4 filing?

The filing shows that the 1,780 shares of Apellis common stock were sold at a price of $22.1872 per share.

Why did Apellis officer Mark DeLong sell 1,780 shares of APLS stock?

The footnotes state that the 1,780 shares were sold to cover tax withholding on Restricted Stock Units that were released on January 12, 2026.

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

After the sale, Mark DeLong beneficially owned 83,058 shares of Apellis common stock.

Does Mark DeLong’s reported Apellis (APLS) ownership include employee stock purchase plan shares?

Yes. The filing notes that DeLong’s 83,058 shares include 893 shares acquired through an ESPP purchase on April 30, 2025.

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

Mark DeLong is identified in the filing as an officer of Apellis, serving as Chief Business & Strat Officer.

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

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Accepted by SEC EDGAR 01/15/2026 - 04:33 PM 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)
01/13/2026

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	01/13/2026		S(1)		1,780	D	$22.1872	83,058(2)	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 January 12, 2026.

2. This includes 893 shares from April 30, 2025 ESPP purchase.

	/s/ David Watson, attorney-in-fact for Mark DeLong	01/15/2026
	** 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.