Philip Mazzara - 17 Aug 2026 Form 4 Insider Report for Astera Labs, Inc. (ALAB)

Reporting relationship: General Counsel and Secretary
Issuer ticker: ALAB
Reported as of: 17 Aug 2026
Net transaction value: -$2,315,754
SEC form: 4
Accepted by SEC: 19 Aug 2026, 18:11:27 UTC
Prior SEC filing: 26 May 2026
Source filing: View source filing
Reporting owner signature: /s/ Philip Mazzara

Key filing fact

Philip Mazzara filed Form 4 for Astera Labs, Inc. (ALAB) on 19 Aug 2026.

Key facts

This page summarizes Philip Mazzara's Form 4 filing for Astera Labs, Inc. (ALAB).
18 reported transactions and 0 derivative rows are listed below.
Accepted by SEC: 19 Aug 2026, 18:11.

Change

Previous filing in this sequence was filed on 26 May 2026.
Current net transaction value: -$2,315,754.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001998163 Primary reporting owner

Mazzara Philip

Relationship: General Counsel and Secretary
Address: C/O ASTERA LABS, INC., 2345 NORTH FIRST STREET, SAN JOSE
Signature: /s/ Philip Mazzara
Signature date: 19 Aug 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

ALAB transaction

Common Stock

Sale

Transaction value: $15,493
Shares: -44
Change %: -0.04%
Price: $352.10
Shares after: 103,299
Date: 17 Aug 2026
Ownership: Direct
Footnotes: F1, F2

ALAB transaction

Common Stock

Sale

Transaction value: $28,801
Shares: -82
Change %: -0.08%
Price: $351.24
Shares after: 103,217
Date: 17 Aug 2026
Ownership: Direct
Footnotes: F1, F3

ALAB transaction

Common Stock

Sale

Transaction value: $54,473
Shares: -156
Change %: -0.15%
Price: $349.19
Shares after: 103,061
Date: 17 Aug 2026
Ownership: Direct
Footnotes: F1, F4

ALAB transaction

Common Stock

Sale

Transaction value: $28,192
Shares: -81
Change %: -0.08%
Price: $348.05
Shares after: 102,980
Date: 17 Aug 2026
Ownership: Direct
Footnotes: F1, F5

ALAB transaction

Common Stock

Sale

Transaction value: $93,347
Shares: -269
Change %: -0.26%
Price: $347.02
Shares after: 102,711
Date: 17 Aug 2026
Ownership: Direct
Footnotes: F1, F6

ALAB transaction

Common Stock

Sale

Transaction value: $68,879
Shares: -199
Change %: -0.19%
Price: $346.13
Shares after: 102,512
Date: 17 Aug 2026
Ownership: Direct
Footnotes: F1, F7

ALAB transaction

Common Stock

Sale

Transaction value: $451,943
Shares: -1,310
Change %: -1.3%
Price: $344.99
Shares after: 101,202
Date: 17 Aug 2026
Ownership: Direct
Footnotes: F1, F8

ALAB transaction

Common Stock

Sale

Transaction value: $98,710
Shares: -287
Change %: -0.28%
Price: $343.94
Shares after: 100,915
Date: 17 Aug 2026
Ownership: Direct
Footnotes: F1, F9

ALAB transaction

Common Stock

Sale

Transaction value: $142,323
Shares: -415
Change %: -0.41%
Price: $342.95
Shares after: 100,500
Date: 17 Aug 2026
Ownership: Direct
Footnotes: F1, F10

ALAB transaction

Common Stock

Sale

Transaction value: $42,714
Shares: -125
Change %: -0.12%
Price: $341.71
Shares after: 100,375
Date: 17 Aug 2026
Ownership: Direct
Footnotes: F1, F11

ALAB transaction

Common Stock

Sale

Transaction value: $69,820
Shares: -205
Change %: -0.2%
Price: $340.58
Shares after: 100,170
Date: 17 Aug 2026
Ownership: Direct
Footnotes: F1, F12

ALAB transaction

Common Stock

Sale

Transaction value: $171,231
Shares: -504
Change %: -0.5%
Price: $339.74
Shares after: 99,666
Date: 17 Aug 2026
Ownership: Direct
Footnotes: F1, F13

ALAB transaction

Common Stock

Sale

Transaction value: $206,536
Shares: -610
Change %: -0.61%
Price: $338.58
Shares after: 99,056
Date: 17 Aug 2026
Ownership: Direct
Footnotes: F1, F14

ALAB transaction

Common Stock

Sale

Transaction value: $269,192
Shares: -797
Change %: -0.8%
Price: $337.76
Shares after: 98,259
Date: 17 Aug 2026
Ownership: Direct
Footnotes: F1, F15

ALAB transaction

Common Stock

Sale

Transaction value: $76,419
Shares: -227
Change %: -0.23%
Price: $336.65
Shares after: 98,032
Date: 17 Aug 2026
Ownership: Direct
Footnotes: F1, F16

ALAB transaction

Common Stock

Sale

Transaction value: $45,617
Shares: -136
Change %: -0.14%
Price: $335.42
Shares after: 97,896
Date: 17 Aug 2026
Ownership: Direct
Footnotes: F1, F17

ALAB transaction

Common Stock

Sale

Transaction value: $180,483
Shares: -540
Change %: -0.55%
Price: $334.23
Shares after: 97,356
Date: 17 Aug 2026
Ownership: Direct
Footnotes: F1, F18

ALAB transaction

Common Stock

Sale

Transaction value: $271,581
Shares: -814
Change %: -0.84%
Price: $333.64
Shares after: 96,542
Date: 17 Aug 2026
Ownership: Direct
Footnotes: F1, F19

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 19 footnotes

Footnote F1

Represents shares of the Issuer's Common Stock required to be sold by the Reporting Person to satisfy tax withholding obligations in connection with the vesting and settlement of restricted stock units previously granted to the Reporting Person. Such sales were automatic and mandated by an election of the Issuer made in advance of the vesting event to require the satisfaction of tax withholding obligations to be funded by a "sell to cover", and does not represent a discretionary trade by the Reporting Person.

Footnote F2

The price reported in Column 4 is a weighted average price. The shares were sold as part of block trades for multiple security holders of the Issuer in multiple transactions at prices ranging from $351.7600 to $352.5000, 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.

Footnote F3

The price reported in Column 4 is a weighted average price. The shares were sold as part of block trades for multiple security holders of the Issuer in multiple transactions at prices ranging from $350.8850 to $351.5000, 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.

Footnote F4

The price reported in Column 4 is a weighted average price. The shares were sold as part of block trades for multiple security holders of the Issuer in multiple transactions at prices ranging from $348.8000 to $349.7300, 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.

Footnote F5

The price reported in Column 4 is a weighted average price. The shares were sold as part of block trades for multiple security holders of the Issuer in multiple transactions at prices ranging from $347.6800 to $348.6300, 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.

Footnote F6

The price reported in Column 4 is a weighted average price. The shares were sold as part of block trades for multiple security holders of the Issuer in multiple transactions at prices ranging from $346.6200 to $347.5600, 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.

Footnote F7

The price reported in Column 4 is a weighted average price. The shares were sold as part of block trades for multiple security holders of the Issuer in multiple transactions at prices ranging from $345.5900 to $346.5050, 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.

Footnote F8

The price reported in Column 4 is a weighted average price. The shares were sold as part of block trades for multiple security holders of the Issuer in multiple transactions at prices ranging from $344.5100 to $345.5000, 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.

Footnote F9

The price reported in Column 4 is a weighted average price. The shares were sold as part of block trades for multiple security holders of the Issuer in multiple transactions at prices ranging from $343.4100 to $344.4000, 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.

Footnote F10

The price reported in Column 4 is a weighted average price. The shares were sold as part of block trades for multiple security holders of the Issuer in multiple transactions at prices ranging from $342.4400 to $343.3800, 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.

Footnote F11

The price reported in Column 4 is a weighted average price. The shares were sold as part of block trades for multiple security holders of the Issuer in multiple transactions at prices ranging from $341.4300 to $342.3800, 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.

Footnote F12

The price reported in Column 4 is a weighted average price. The shares were sold as part of block trades for multiple security holders of the Issuer in multiple transactions at prices ranging from $340.2200 to $341.2150, 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.

Footnote F13

The price reported in Column 4 is a weighted average price. The shares were sold as part of block trades for multiple security holders of the Issuer in multiple transactions at prices ranging from $339.2100 to $340.2000, 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.

Footnote F14

The price reported in Column 4 is a weighted average price. The shares were sold as part of block trades for multiple security holders of the Issuer in multiple transactions at prices ranging from $338.2000 to $339.1900, 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.

Footnote F15

The price reported in Column 4 is a weighted average price. The shares were sold as part of block trades for multiple security holders of the Issuer in multiple transactions at prices ranging from $337.2600 to $338.1850, 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.

Footnote F16

The price reported in Column 4 is a weighted average price. The shares were sold as part of block trades for multiple security holders of the Issuer in multiple transactions at prices ranging from $336.0450 to $337.0000, 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.

Footnote F17

The price reported in Column 4 is a weighted average price. The shares were sold as part of block trades for multiple security holders of the Issuer in multiple transactions at prices ranging from $335.2425 to $335.9750, 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.

Footnote F18

The price reported in Column 4 is a weighted average price. The shares were sold as part of block trades for multiple security holders of the Issuer in multiple transactions at prices ranging from $333.8100 to $334.8050, 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.

Footnote F19

The price reported in Column 4 is a weighted average price. The shares were sold as part of block trades for multiple security holders of the Issuer in multiple transactions at prices ranging from $333.3600 to $333.4250, 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.