[Form 4] ANAPTYSBIO, INC Insider Trading Activity

Rhea-AI Filing Summary

Eric J. Loumeau, Chief Legal Officer of AnaptysBio, Inc. (ANAB), reported both purchases and sales of company common stock on 09/30/2025. He acquired 5,000 shares by exercising employee stock options at an exercise price of $14.02 and an additional 1,325 shares under the company ESPP included in the reported holdings, bringing his post-transaction direct ownership to 17,328 shares. He also sold 8,240 shares at $29.00 per share under a 10b5-1 trading plan adopted April 11, 2025.

The Form 4 shows he retains outstanding options to purchase 68,000 shares exercisable under the option described and additional unvested options aggregating up to 422,310 shares that vest per their terms. Transactions were routine insider activity documented under Section 16 reporting rules.

Positive

• Exercise of options converted compensation into 5,000 common shares at a $14.02 exercise price
• ESPP participation added 1,325 shares to the reporting person's holdings
• Sale executed under 10b5-1 plan, indicating a pre-established trading plan that provides compliance clarity

Negative

• Sale of 8,240 shares reduced direct holdings from the pre-transaction level to 9,088 shares before accounting for acquisitions
• Significant unexercised option pool disclosed (68,000 exercisable plus up to 422,310 additional options), representing potential future dilution

Insights

Securities Analyst

TL;DR: Routine insider option exercise combined with a planned sale under a 10b5-1 plan; net effect modest given total outstanding options.

The reporting shows a simultaneous exercise of options and an ESPP acquisition totaling 6,325 shares and a sale of 8,240 shares executed under a pre-established 10b5-1 plan. The exercise price of $14.02 versus the sale price of $29.00 indicates the sale likely occurred at a profit relative to the exercised lots. The filing discloses materially larger unexercised option holdings (68,000 listed plus up to 422,310 additional options) which could affect future dilution but are disclosed with vesting schedules as required.

Corporate Governance Expert

TL;DR: Disclosure follows standard Section 16 requirements; sale executed under a 10b5-1 plan reduces regulatory scrutiny.

The Form 4 documents compliant reporting of insider transactions, including exercise/vest schedules and identification of the 10b5-1 plan that governed the sale. The filing clarifies direct ownership and nature of indirect holdings and includes ESPP participation. No unexplained transfers or unusual forms of disposition are present in the record provided.

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).

1. Name and Address of Reporting Person^*

LOUMEAU ERIC J

(Last) (First) (Middle)

C/O ANAPTYSBIO, INC.

10770 WATERIDGE CIRCLE, SUITE 210

(Street)

SAN DIEGO CA 92121

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
ANAPTYSBIO, INC [ ANAB ]

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

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	CHIEF LEGAL OFFICER

3. Date of Earliest Transaction (Month/Day/Year)
09/30/2025

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	09/30/2025		M		5,000	A	$14.02	17,328(1)	D
Common Stock	09/30/2025		S(2)		8,240	D	$29	9,088	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
Employee Stock Option (right to buy)	$14.02	09/30/2025		M			5,000	(3)	12/05/2029	Common Stock	5,000	$0	68,000(4)	D

Explanation of Responses:

1. Includes the acquisition of 1,325 shares acquired under the Company's ESPP.

2. The transactions reported on this Form 4 were effected pursuant to a 10b5-1 trading plan adopted by the reporting person dated April 11, 2025.

3. The stock option vested and is exercisable as to 25% of the shares subject to the option on December 6, 2020, and thereafter vests as to 1/48th of the shares in equal monthly installments, until such time as the option is 100% vested, subject to the continuing employment of the Reporting Person on each vesting date.

4. In addition to the remaining options to purchase 68,000 shares of common stock as set forth in Table II, the Reporting Person also holds additional options to purchase up to an aggregate of 422,310 shares of common stock, which options vest according to their terms.

	/s/ Eric Loumeau	10/01/2025
	** 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.

FAQ

What insider transactions did ANAB Chief Legal Officer Eric Loumeau report on 09/30/2025?

The Form 4 reports a 5,000-share option exercise at $14.02, 1,325 shares acquired via the ESPP, and a sale of 8,240 shares at $29.00.

Were any sales executed under a trading plan for ANAB insider transactions?

Yes. The sale of 8,240 shares was effected pursuant to a 10b5-1 trading plan dated April 11, 2025.

How many ANAB option shares does the reporting person still hold?

The Form 4 shows 68,000 remaining exercisable options under the reported option plus additional options aggregating up to 422,310 that vest according to their terms.

What exercise price and sale price are reported in the Form 4 for ANAB transactions?

The reported option exercise price is $14.02 and the reported sale price is $29.00 per share.

Does the filing indicate whether the transactions were direct or indirect?

Yes. All reported transactions and holdings in this Form 4 are shown as Direct (D) beneficial ownership.