<div id="readability-page-1"><div><p><span>Chung Jane Chief Executive Officer of Sutro Biopharma Inc [STRO] filed a Form 4 on December 16, 2025 with the Securities and Exchange Commission disclosing the following changes in ownership:</span></p><div><table><tbody><tr><th><span>Date</span></th><th><span>Transaction</span></th><th><span>Shares</span></th><th><span>Price</span></th><th><span>Value</span></th></tr><tr><td><span>12/12/25</span></td><td><span>Exercise(1)</span></td><td><span>2,500</span></td><td><span>$0.00</span></td><td><span>N/A</span></td></tr><tr><td><span>12/12/25</span></td><td><span>Surrender(2)</span></td><td><span>894</span></td><td><span>$8.02</span></td><td><span>$7,165</span></td></tr></tbody></table></div><p><span>Ending Holdings: 13,891 - Direct</span></p><div><table><tbody><tr><td><span>(1)</span></td><td><span>Exercised 2.0 years before expiration date.</span></td></tr><tr><td><span>(2)</span></td><td><span>Surrender of shares back to company to pay option exercise cost and/or resulting tax liability.</span></td></tr></tbody></table></div><p><span>For a free trial, or to learn more about our insider trading analysis and data services, please visit http://www.washingtonservice.com or contact us at (301) 913-5100 or send an email to info@washingtonservice.com.</span></p><p><span>Founded in 1970, The Washington Service provides securities professionals with financial, economic and public policy research and data.</span></p><span> </span></div></div>

STRO

<p>CEO Chung Jane of Sutro Biopharma Inc filed a Form 4 with the SEC, revealing changes in ownership. On December 12, 2025, Chung exercised 2,500 shares and surrendered 894 shares to cover option exercise costs and tax liabilities. Ending holdings are 13,891 shares directly. The Washington Service offers insider trading analysis and data services.</p>

CEO Chung Acquires 1,606 Of Sutro Biopharma Inc [STRO]