Astera Labs counsel sells 6,801 shares for taxes
Astera Labs, Inc. (ALAB) reported that its General Counsel and Secretary, Philip Mazzara, had multiple sales of common stock on August 17, 2026.
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Form Type
4
Rhea-AI Filing Summary
Astera Labs, Inc. (ALAB) reported that its General Counsel and Secretary, Philip Mazzara, had multiple sales of common stock on August 17, 2026. In total, 6,801 shares were sold in open-market block trades at reported per-share prices between $333.6377 and $352.1027.
According to the company’s disclosure, these shares were sold to satisfy tax withholding obligations arising from the vesting and settlement of previously granted restricted stock units. The company states the sales were automatic under a pre-established “sell to cover” election made by Astera Labs and did not represent discretionary trading by Mazzara.
Insights
Analyzing...
Insider Trade Summary
Net Seller: 6,801 shares
Net Sell
18 txns
Insider
Mazzara Philip
Role
General Counsel and Secretary
Sold
6,801 shs ($2.32M)
| Type | Security | Shares | Price | Value |
|---|---|---|---|---|
| Sale | Common Stock F1, F2 | 44 | $352.1027 | $15K |
| Sale | Common Stock F1, F3 | 82 | $351.2367 | $29K |
| Sale | Common Stock F1, F4 | 156 | $349.1871 | $54K |
| Sale | Common Stock F1, F5 | 81 | $348.053 | $28K |
| Sale | Common Stock F1, F6 | 269 | $347.0152 | $93K |
| Sale | Common Stock F1, F7 | 199 | $346.1272 | $69K |
| Sale | Common Stock F1, F8 | 1,310 | $344.9945 | $452K |
| Sale | Common Stock F1, F9 | 287 | $343.9357 | $99K |
| Sale | Common Stock F1, F10 | 415 | $342.9479 | $142K |
| Sale | Common Stock F1, F11 | 125 | $341.7085 | $43K |
| Sale | Common Stock F1, F12 | 205 | $340.5846 | $70K |
| Sale | Common Stock F1, F13 | 504 | $339.7447 | $171K |
| Sale | Common Stock F1, F14 | 610 | $338.5835 | $207K |
| Sale | Common Stock F1, F15 | 797 | $337.7572 | $269K |
| Sale | Common Stock F1, F16 | 227 | $336.6463 | $76K |
| Sale | Common Stock F1, F17 | 136 | $335.4178 | $46K |
| Sale | Common Stock F1, F18 | 540 | $334.227 | $180K |
| Sale | Common Stock F1, F19 | 814 | $333.6377 | $272K |
Holdings After Transaction:
Common Stock — 96,542 shares (Direct)
Footnotes (19)
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
Key Figures
Total shares sold: 6,801 shares
Highest reported sale price: $352.1027 per share
Lowest reported sale price: $333.6377 per share
+2 more
5 metrics
Total shares sold
6,801 shares
Aggregate non-derivative common shares sold by Philip Mazzara on August 17, 2026
Highest reported sale price
$352.1027 per share
Maximum per-share sale price among the reported August 17, 2026 transactions
Lowest reported sale price
$333.6377 per share
Minimum per-share sale price among the reported August 17, 2026 transactions
Number of sale transactions
18 transactions
Separate open-market or private sales of common stock reported for August 17, 2026
Net buy/sell direction
-6,801 shares
Net effect of reported non-derivative transactions (all sales) for this Form 4
Key Terms
sell to cover, restricted stock units, weighted average price, tax withholding obligations
4 terms
sell to cover financial
"require the satisfaction of tax withholding obligations to be funded by a "sell to cover""
Sell to cover is when a person who receives company stock through options or awards sells just enough shares immediately to pay required taxes, exercise costs, or fees, keeping the rest. Think of it like cashing part of a bonus to cover the tax bill so you can keep the remainder. For investors, it can create predictable small selling pressure and slightly change the number of shares actually held by insiders without increasing long‑term dilution.
restricted stock units financial
"connection with the vesting and settlement of restricted stock units previously granted"
Restricted stock units are a type of company reward where employees are promised shares of stock, but they only fully own these shares after meeting certain conditions, like staying with the company for a set time. They matter because they can become valuable assets and are often used to motivate employees to help the company succeed.
weighted average price financial
"The price reported in Column 4 is a weighted average price."
Weighted average price is the average price of a security where each trade or component is counted according to its size, so bigger trades pull the average more than smaller ones. Think of it like calculating the average cost of a grocery haul where items you bought more of have greater influence on the final per-item cost. Investors use it to understand the true average price paid or received, judge execution quality, and compare trading performance against market movement.
tax withholding obligations financial
"shares of the Issuer's Common Stock required to be sold ... to satisfy tax withholding obligations"
FAQ
AI-generated questions and answers. How Rhea-AI works. Not financial advice.
What insider transaction did ALAB report for Philip Mazzara on August 17, 2026?
Astera Labs (ALAB) reported that Philip Mazzara sold 6,801 shares of common stock on August 17, 2026. The company states these automatic sales covered tax withholding obligations from vested restricted stock units, under a pre-established “sell to cover” election.
How many sale transactions did the ALAB Form 4 report for Philip Mazzara?
The Form 4 reports 18 separate sale transactions of Astera Labs common stock for Philip Mazzara on August 17, 2026. All are coded as open-market or private sales (code S) and together total 6,801 shares sold to cover tax withholding.
Were Philip Mazzara’s ALAB stock sales part of block trades?
Yes. The filing states the shares were sold as part of block trades executed for multiple Astera Labs security holders. Reported prices are given as weighted averages, with additional price ranges provided for each block in the footnotes.
Did Astera Labs indicate Philip Mazzara’s ALAB sales were made under a trading plan?
Astera Labs indicates the sales followed a company election requiring a “sell to cover” for tax withholding on vested RSUs. The disclosure specifies the sales were automatic and did not represent discretionary trades by Philip Mazzara.
AI-generated analysis. How Rhea-AI works. Not financial advice.
