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Sutro Biopharma, Inc.

STRO
Exchange
Nasdaq
Industry
Biological Products, (No Diagnostic Substances)
SEC CIK
0001382101

No open-market purchases or sales by Sutro Biopharma, Inc. insiders were filed in the last 90 days; 100 institutions reported holding it in 13F filings for Q2 2026, worth $545.7M in total; no superinvestor holds it.

Holders of 5% or more of STRO

Holders whose latest Schedule 13D or 13G filing reports 5% or more of Sutro Biopharma, Inc., largest stake first. The change is against the holder's previous filing.

Holders of 5% or more of STRO
HolderLatest formStakeChangeFirst filedLatest filingFiling
Perceptive Advisors LLC13G/A7.90%1.30M shares+2.50 ppfrom 5.40%Apr 21, 20262 filingsAug 14, 2026SEC
Biotechnology Value Fund L P13G7.60%1.25M shares–Feb 12, 20215 filingsFeb 18, 2026SEC
Affinity Asset Advisors, LLC13G/A6.50%1.07M shares−2.30 ppfrom 8.80%Oct 23, 20253 filingsMay 14, 2026SEC
BlackRock, Inc.13G6.40%1.07M sharesNewJul 30, 20261 filingJul 30, 2026SEC
Samsara BioCapital, L.P.13G6.40%1.06M sharesNewMay 15, 20261 filingMay 15, 2026SEC
Millennium Management LLC13G5.60%4.72M shares–Jul 8, 20223 filingsJun 30, 2025SEC
Kynam Capital Management, LP13G/A5.27%0 shares−1.17 ppfrom 6.44%May 15, 20252 filingsMay 15, 2026SEC
Coastlands Capital LP13G5.14%852.7K sharesNewNov 9, 20261 filingNov 9, 2026SEC

Stakes are as of each holder's latest filing. Holders whose last filing was in the old format (before December 18, 2024) have no stake on record and are not listed, and after an acquisition or delisting holders usually stop filing.

13D and 13G filings

59 Schedule 13D and 13G filings on Sutro Biopharma, Inc., newest first, including old-format filings without a stake.

Schedule 13D and 13G filings on STRO
Filed (ET)FilerFormStakeChangeEvent dateFiling
Nov 9, 20261:23 PM ETCoastlands Capital LPand 4 others13G5.14%852.7K sharesNewNov 5, 2026SEC
Aug 14, 20265:21 PM ETPerceptive Advisors LLCand 2 others13G/A7.90%1.30M shares+2.50 ppfrom 5.40%Jun 30, 2026SEC
Aug 14, 20264:10 PM ETPoint72 Asset Management, L.P.and 2 others13G/A1.40%237.8K shares−4.30 ppfrom 5.70%Below 5%Jun 30, 2026SEC
Jul 30, 202611:18 AM ETBlackRock, Inc.13G6.40%1.07M sharesNewJun 30, 2026SEC
May 15, 20264:39 PM ETSamsara BioCapital, L.P.and 4 others13G6.40%1.06M sharesNewFeb 11, 2026SEC
May 15, 20264:01 PM ETKynam Capital Management, LPand 2 others13G/A5.27%0 shares−1.17 ppfrom 6.44%Mar 31, 2026SEC
May 14, 20264:13 PM ETAffinity Asset Advisors, LLCand 1 other13G/A6.50%1.07M shares−2.30 ppfrom 8.80%Mar 31, 2026SEC
May 1, 20264:10 PM ETPoint72 Asset Management, L.P.and 2 others13G5.70%946.8K shares–Apr 24, 2026SEC
Apr 21, 20265:49 PM ETMillennium Management LLCand 2 others13G/A1.30%210.4K shares–Below 5%Mar 31, 2026SEC
Apr 21, 20264:19 PM ETPerceptive Advisors LLCand 2 others13G5.40%898.0K sharesNewApr 14, 2026SEC
Feb 18, 20267:49 PM ETBiotechnology Value Fund L Pand 9 others13G7.60%1.25M shares–Feb 10, 2026SEC
Feb 13, 20264:50 PM ETSuvretta Capital Management, LLCand 2 others13G/A0.00%0 shares0.00 ppfrom 0.00%Below 5%Dec 31, 2025SEC
Feb 13, 20264:49 PM ETSuvretta Capital Management, LLCand 2 others13G/A0.00%0 shares−7.70 ppfrom 7.70%Below 5%Dec 31, 2025SEC
Jan 29, 20267:58 PM ETAffinity Asset Advisors, LLCand 1 other13G/A8.80%748.4K shares+1.03 ppfrom 7.77%Jan 22, 2026SEC
Oct 23, 20254:07 PM ETAffinity Asset Advisors, LLCand 1 other13G7.77%6.58M sharesNewOct 16, 2025SEC
Aug 14, 20256:10 PM ETRa Capital Management, L.P.and 3 others13G/A0.00%0 shares−5.30 ppfrom 5.30%Below 5%Jun 30, 2025SEC
Aug 13, 20258:47 PM ETSuvretta Capital Management, LLCand 2 others13G/A7.70%6.49M shares–Jun 30, 2025SEC
Jul 29, 20252:41 PM ETVanguard Group Inc13G/A4.87%4.12M shares–Below 5%Jun 30, 2025SEC
Jul 16, 20257:02 PM ETBlackRock, Inc.13G/A2.50%2.09M shares−4.80 ppfrom 7.30%Below 5%Jun 30, 2025SEC
Jun 30, 20254:36 PM ETMillennium Management LLCand 2 others13G5.60%4.72M shares–Jun 27, 2025SEC
May 15, 202511:39 AM ETKynam Capital Management, LPand 2 others13G6.44%0 sharesNewMar 31, 2025SEC
Apr 17, 20259:35 AM ETBlackRock, Inc.13G/A7.30%6.14M shares–Mar 31, 2025SEC
Apr 4, 20254:32 PM ETRa Capital Management, L.P.and 3 others13G5.30%4.43M sharesNewMar 28, 2025SEC
Nov 14, 2024Biotechnology Value Fund L P13G/AOld format–––SEC
Nov 14, 2024Point72 Asset Management, L.P.13G/AOld format–––SEC
Nov 13, 2024Rubric Capital Management LP13G/AOld format–––SEC
Nov 12, 2024Vanguard Group Inc13G/AOld format–––SEC
Nov 12, 2024Adage Capital Management, L.P.13G/AOld format–––SEC
Nov 4, 2024Integrated Core Strategies (US) LLC13G/AOld format–––SEC
Nov 4, 2024Vanguard Group Inc13G/AOld format–––SEC
Apr 5, 2024Point72 Asset Management, L.P.13GOld format–New–SEC
Feb 13, 2024Suvretta Capital Management, LLC13G/AOld format–––SEC
Feb 12, 2024Rubric Capital Management LP13G/AOld format–––SEC
Feb 7, 2024Adage Capital Partners GP, L.L.C.13G/AOld format–––SEC
Jan 24, 20245:23 PM ETBlackRock Inc.13G/AOld format–––SEC
Jan 17, 2024Integrated Core Strategies (US) LLC13GOld format–New–SEC
Oct 10, 2023Adage Capital Partners GP, L.L.C.13GOld format–New–SEC
Feb 14, 2023Eventide Asset Management, LLC13G/AOld format–––SEC
Feb 14, 2023Biotechnology Value Fund L P13G/AOld format–––SEC
Feb 13, 2023Suvretta Capital Management, LLC13G/AOld format–––SEC
Feb 10, 2023Rubric Capital Management LP13GOld format–New–SEC
Feb 7, 20232:55 PM ETBlackRock Inc.13G/AOld format–––SEC
Feb 1, 2023Franklin Resources Inc13G/AOld format–––SEC
Jan 23, 2023Millennium Management LLC13G/AOld format–––SEC
Jul 8, 2022Millennium Management LLC13GOld format–New–SEC
Feb 14, 2022Eventide Asset Management, LLC13G/AOld format–––SEC
Feb 11, 2022Suvretta Capital Management, LLC13G/AOld format–––SEC
Feb 4, 2022Franklin Resources Inc13GOld format–New–SEC
Feb 2, 20227:18 PM ETBlackRock Inc.13G/AOld format–––SEC
Jan 18, 2022Biotechnology Value Fund L P13GOld format–––SEC

Form 144: proposed insider sales

3 notices from officers, directors and other affiliates planning to sell Sutro Biopharma, Inc. shares, newest first.

Form 144 notices for STRO
Filed (ET)SellerShares to sellMarket valuePlanned saleBrokerFiling
Jan 20, 20264:17 PM ETBarbara LeymanFormer officer8.93K$131.0KJan 20, 2026Morgan Stanley Smith Barney LLC Executive Financial ServicesSEC
Jan 29, 20245:14 PM ETNicki J VasquezOfficer12.2K$60.9KJan 29, 202410b5-1Morgan Stanley Smith Barney LLC Executive Financial ServicesSEC
Aug 25, 20234:46 PM ETShtylla BrunildaOfficer27.0K$156.3KAug 25, 2023ETRADE FINANCIAL CORPORATIONSEC