Astera Labs (ALAB) General Counsel Sells 10,000 Shares Under 10b5-1

Rhea-AI Filing Summary

Philip Mazzara, General Counsel and Secretary of Astera Labs, Inc. (ALAB), sold 10,000 shares of company common stock on 08/28/2025 under a pre-established Rule 10b5-1 trading plan adopted May 29, 2025. The sales occurred in multiple transactions at prices ranging approximately from $182.55 to $190.91 per share; weighted-average prices are reported for several tranches. Following these dispositions, the reporting person’s beneficial ownership is reported as 161,573 shares, held directly. The Form 4 discloses that the transactions executed automatically under the trading plan.

Positive

• Sales executed under a Rule 10b5-1 trading plan, which indicates pre-established, automated transactions rather than discretionary insider trading
• Reporting person retains significant direct ownership of 161,573 shares after the dispositions

Negative

• Insider sold 10,000 shares in a single reported transaction date, which could be perceived negatively by some investors
• Form 4 lacks aggregate proceeds disclosure (only per-tranche prices and weighted averages are provided)

Insights

Corporate Governance Expert

TL;DR: Insider sold 10,000 shares via a pre-set 10b5-1 plan, indicating automated, non-discretionary disposal rather than ad hoc selling.

The filing shows a controlled disposition executed under a Rule 10b5-1 plan adopted May 29, 2025. Use of such a plan generally reduces concerns about trading on material nonpublic information because transactions occur pursuant to preset instructions. The remaining direct ownership of 161,573 shares keeps the reporting person materially invested in the company. No derivative holdings or additional disclosures of other relationships are provided in this Form 4.

Securities Analyst

TL;DR: 10,000 shares sold across multiple tranches at ~$182.55–$190.91, yielding staged disposals under a prearranged plan.

The specifics show multiple weighted-average prices reported and a clear statement that sales were automatic under a 10b5-1 plan. Transaction concentration on a single date (08/28/2025) suggests plan parameters allowed intraday executions. The filing does not disclose proceeds aggregate or motivation beyond the plan, so assessment of financial impact on the individual or signal to investors is limited.

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).

X

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^*

Mazzara Philip

(Last) (First) (Middle)

C/O ASTERA LABS, INC.

2345 NORTH FIRST STREET

(Street)

SAN JOSE CA 95131

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Astera Labs, Inc. [ ALAB ]

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

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	General Counsel and Secretary

3. Date of Earliest Transaction (Month/Day/Year)
08/28/2025

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	08/28/2025		S(1)		100	D	$182.55	171,473	D
Common Stock	08/28/2025		S(1)		339	D	$185.6981(2)	171,134	D
Common Stock	08/28/2025		S(1)		800	D	$186.3687(3)	170,334	D
Common Stock	08/28/2025		S(1)		1,716	D	$187.5665(4)	168,618	D
Common Stock	08/28/2025		S(1)		2,993	D	$188.8774(5)	165,625	D
Common Stock	08/28/2025		S(1)		2,852	D	$189.6511(6)	162,773	D
Common Stock	08/28/2025		S(1)		1,200	D	$190.4962(7)	161,573	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. The sales reported in this Form 4 occurred automatically pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 29, 2025.

2. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $184.9400 to $185.9200, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the U.S. Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

3. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $186.0500 to $187.0000, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the U.S. Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

4. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $187.0900 to $188.0700, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the U.S. Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

5. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $188.1900 to $189.1800, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the U.S. Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

6. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $189.2000 to $190.0600, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the U.S. Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

7. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $190.2100 to $190.9100, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the U.S. Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

Remarks:

	/s/ Philip Mazzara	09/02/2025
	** 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 did Philip Mazzara (ALAB) report on Form 4?

The Form 4 reports that Philip Mazzara, General Counsel and Secretary of Astera Labs (ALAB), disposed of 10,000 shares of common stock on 08/28/2025 under a Rule 10b5-1 trading plan.

How many shares does the insider own after the reported sales?

Following the reported transactions the filing shows the reporting person beneficially owns 161,573 shares (direct ownership).

Were the sales part of a 10b5-1 plan for ALAB insider trades?

Yes. The sales occurred automatically pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on May 29, 2025.

What price range did the ALAB shares sell for?

The transactions occurred at prices reported from approximately $182.55 up to about $190.91 per share, with several weighted-average prices disclosed for tranches.

How many shares were sold in each tranche?

The Form 4 lists sales of 100, 339, 800, 1,716, 2,993, 2,852, and 1,200 shares across multiple tranches, totaling 10,000 shares.