Vault-13

SUTRO BIOPHARMA INC STRO

COM SHS · Common Stock · CUSIP 869367201

97 institutional holders +26 vs Q1 2026
16,480,06116.5m shares reported held*
99.4% of all shares outstanding*
$545.7mreported value*
41 new 24 added 18 reduced 14 sold out net bought ≈ $76.9m (+2.4m shares)

* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once. Holder counts are more reliable. Shares outstanding: 16.6m as of 2026-08-07, from the company's own SEC filing; the percentage can still exceed 100%: lent-out shares are counted by the lender and the buyer, and some reports overlap without saying so. Implied quarter-end price ≈ $33.11. Options: 2 managers hold calls ($371.8k notional), 2 hold puts ($371.8k).

Trends to Q2 2026

Institutional holders

Managers reporting a position, each quarter

050100Q4 25: 56Q1 26: 71Q2 26: 9797Q4 25Q1 26Q2 26
Numbers
QuarterHolders
Q4 202556
Q1 202671
Q2 202697

Buyers vs sellers

Managers adding to or starting a position, vs cutting or selling out

Bought or addedCut or sold out
1000100Q1 26: 44 bought or addedQ1 26: 21 cut or sold outQ1 26Q2 26: 65 bought or addedQ2 26: 32 cut or sold outQ2 26
Numbers
QuarterBought or addedCut or sold out
Q1 20264421
Q2 20266532

Calls vs puts

Options held, notional value, last 4 quarters. P/C = puts ÷ calls

CallsPuts
$0$1m$2m$3mQ3 25 calls: $0Q3 25 puts: $0Q3 25P/C —Q4 25 calls: $34.7kQ4 25 puts: $8.1kQ4 25P/C 0.23Q1 26 calls: $0Q1 26 puts: $2.2mQ1 26P/C —Q2 26 calls: $371.8kQ2 26 puts: $371.8kQ2 26P/C 1.00
Numbers
QuarterCallsPutsP/C
Q3 2025$0$0—
Q4 2025$34.7k$8.1k0.23
Q1 2026$0$2.2m—
Q2 2026$371.8k$371.8k1.00

Biggest buyers

BlackRock, Inc. Added +889,971+890.0k
PERCEPTIVE ADVISORS LLC Added +589,539+589.5k
Merck & Co., Inc. New +272,351+272.4k
STATE STREET CORP Added +253,861+253.9k
Balyasny Asset Management L.P. Added +245,370+245.4k
AMERIPRISE FINANCIAL INC New +244,669+244.7k
GEODE CAPITAL MANAGEMENT, LLC Added +218,306+218.3k
VANGUARD PORTFOLIO MANAGEMENT LLC New +197,562+197.6k
Nuveen, LLC New +167,997+168.0k
JPMORGAN CHASE & CO New +159,627+159.6k

Biggest sellers

RA CAPITAL MANAGEMENT, L.P. Sold out -715,307-715.3k
Point72 Asset Management, L.P. Reduced -454,284-454.3k
ADAGE CAPITAL PARTNERS GP, L.L.C. Sold out -200,000-200.0k
Opaleye Management Inc. Sold out -190,671-190.7k
UBS Group AG Reduced -184,359-184.4k
EVENTIDE ASSET MANAGEMENT, LLC Reduced -130,045-130.0k
ADAR1 Capital Management, LLC Reduced -120,427-120.4k
SUSQUEHANNA INTERNATIONAL GROUP, LLP Reduced -76,476-76.5k
Eversept Partners, LP Sold out -73,161-73.2k
Burkehill Global Management, LP Sold out -71,530-71.5k

Biggest calls

SUSQUEHANNA INTERNATIONAL GROUP, LLP New $368.5k11.1k shares
SIMPLEX TRADING, LLC New $3.3k100 shares

Biggest puts

SUSQUEHANNA INTERNATIONAL GROUP, LLP Reduced $365.2k11.0k shares
SIMPLEX TRADING, LLC Reduced $6.6k200 shares

Options at notional value: the value of the shares the contracts control, as filers report them, not what the options cost. Not included in the holders, shares or buying above.

Major shareholders (over 5%)

Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.

HolderStakeChangeShares Last filed
PERCEPTIVE ADVISORS LLC 13G · passive investor +2.5 pts · filed 2026-08-14 7.9% +2.5 pts 1.3m≈ $43.3m 2026-08-14
BIOTECHNOLOGY VALUE FUND L P 13G · passive investor new · filed 2026-02-18 7.6% new 1.3m≈ $41.6m 2026-02-18
Affinity Asset Advisors, LLC 13G · institution -2.3 pts · filed 2026-05-14 6.5% -2.3 pts 1.1m≈ $35.5m 2026-05-14
BlackRock, Inc. 13G · institution new · filed 2026-07-30 6.4% new 1.1m≈ $35.4m 2026-07-30
Samsara BioCapital, L.P. 13G · passive investor new · filed 2026-05-15 6.4% new 1.1m≈ $35.3m 2026-05-15

Fell to 5% or below in the last year: Point72 Asset Management, L.P. (1.4%, 2026-08-14), MILLENNIUM MANAGEMENT LLC (1.3%, 2026-04-21)

Insider purchases and sales since 1 Apr 2026

Shares bought or sold by the company's own officers, directors and 10% owners, in the open market or privately, as they reported to the SEC on Form 4 (due within two business days of the trade). Grants, option exercises, shares withheld for tax and gifts aren't included.

Officers and directors buying vs selling

Number of people, by quarter (10% owners not included)

BuyingSelling
505Q4 24: 0 buyingQ4 24: 0 sellingQ1 25: 0 buyingQ1 25: 0 sellingQ1 25Q2 25: 0 buyingQ2 25: 0 sellingQ3 25: 0 buyingQ3 25: 0 sellingQ3 25Q4 25: 5 buyingQ4 25: 0 sellingQ1 26: 0 buyingQ1 26: 0 sellingQ1 26Q2 26: 0 buyingQ2 26: 0 sellingQ3 26: 0 buyingQ3 26: 0 sellingQ3 26
Numbers
QuarterBuyingBoughtSellingSoldSold under a plan
Q4 20240—0——
Q1 20250—0——
Q2 20250—0——
Q3 20250—0——
Q4 20255—0——
Q1 20260—0——
Q2 20260—0——
Q3 20260—0——

None reported since 1 Apr 2026.

Holders, Q2 2026

#ManagerLocationShares Value% of their portfolioChangeShares change
1 PERCEPTIVE ADVISORS LLC 0.67% of their portfolio NEW YORK, NY 1,304,8461.3m $43.3m $43.3m 0.67% Added +589.5k +589,539
2 BVF INC/IL 1.06% of their portfolio San Francisco, CA 1,251,7881.3m $41.6m $41.6m 1.06% Unchanged
3 Affinity Asset Advisors, LLC 1.90% of their portfolio NEW YORK, NY 1,172,4871.2m $38.9m $38.9m 1.90% Added +103.0k +102,968
4 BlackRock, Inc. 0.00% of their portfolio New York, NY 1,122,6551.1m $37.3m $37.3m 0.00% Added +890.0k +889,971
5 SAMSARA BIOCAPITAL, LLC 2.90% of their portfolio PALO ALTO, CA 1,062,8721.1m $35.3m $35.3m 2.90% Unchanged
6 Kynam Capital Management, LP 1.60% of their portfolio PRINCETON, NJ 872,558872.6k $29.0m $29.0m 1.60% Unchanged
7 ORBIMED ADVISORS LLC 0.47% of their portfolio New York, NY 743,944743.9k $24.7m $24.7m 0.47% Reduced -57.2k -57,200
8 Balyasny Asset Management L.P. 0.04% of their portfolio Chicago, IL 711,162711.2k $23.6m $23.6m 0.04% Added +245.4k +245,370
9 VANGUARD CAPITAL MANAGEMENT LLC 0.00% of their portfolio MALVERN, PA 694,219694.2k $23.0m $23.0m 0.00% Reduced -26.2k -26,223
10 EVENTIDE ASSET MANAGEMENT, LLC 0.26% of their portfolio Boston, MA 585,262585.3k $19.4m $19.4m 0.26% Reduced -130.0k -130,045
11 Velan Capital Investment Management LP 10.42% of their portfolio ALPHARETTA, GA 512,160512.2k $17.0m $17.0m 10.42% Unchanged
12 Woodline Partners LP 0.05% of their portfolio San Francisco, CA 458,029458.0k $15.2m $15.2m 0.05% Added +588 +588
13 ADAR1 Capital Management, LLC 0.63% of their portfolio AUSTIN, TX 404,014404.0k $13.4m $13.4m 0.63% Reduced -120.4k -120,427
14 GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio BOSTON, MA 389,692389.7k $12.9m $12.9m 0.00% Added +218.3k +218,306
15 ACADIAN ASSET MANAGEMENT LLC 0.01% of their portfolio Boston, MA 373,839373.8k $12.4m $12.4m 0.01% Added +38.0k +38,026
16 MILLENNIUM MANAGEMENT LLC 0.01% of their portfolio NEW YORK, NY 365,972366.0k $12.2m $12.2m 0.01% Added +155.6k +155,594
17 STATE STREET CORP 0.00% of their portfolio BOSTON, MA 305,979306.0k $10.2m $10.2m 0.00% Added +253.9k +253,861
18 Merck & Co., Inc. 1.72% of their portfolio RAHWAY, NJ 272,351272.4k $9.0m $9.0m 1.72% New
19 ACUTA CAPITAL PARTNERS, LLC 6.25% of their portfolio REDWOOD CITY, CA 270,251270.3k $9.0m $9.0m 6.25% Added +826 +826
20 AMERIPRISE FINANCIAL INC 0.00% of their portfolio MINNEAPOLIS, MN 244,669244.7k $8.1m $8.1m 0.00% New
21 Point72 Asset Management, L.P. 0.01% of their portfolio STAMFORD, CT 237,827237.8k $7.9m $7.9m 0.01% Reduced -454.3k -454,284
22 KVP Capital Advisors, LP 5.52% of their portfolio SAN FRANCISCO, CA 226,575226.6k $7.5m $7.5m 5.52% Unchanged
23 UBS Group AG 0.00% of their portfolio ZURICH, V8 208,512208.5k $6.9m $6.9m 0.00% Reduced -184.4k -184,359
24 TWO SIGMA INVESTMENTS, LP 0.01% of their portfolio NEW YORK, NY 201,688201.7k $6.7m $6.7m 0.01% Added +136.5k +136,512
25 VANGUARD PORTFOLIO MANAGEMENT LLC 0.00% of their portfolio MALVERN, PA 197,562197.6k $6.6m $6.6m 0.00% New
26 MARSHALL WACE, LLP 0.00% of their portfolio LONDON, X0 175,246175.2k $5.8m $5.8m 0.00% Reduced -47.4k -47,388
27 Nuveen, LLC 0.00% of their portfolio CHARLOTTE, NC 167,997168.0k $5.6m $5.6m 0.00% New
28 JPMORGAN CHASE & CO 0.00% of their portfolio NEW YORK, NY 159,627159.6k $5.3m $5.3m 0.00% New
29 Seven Fleet Capital Management LP 0.63% of their portfolio MOUNTAIN VIEW, CA 159,118159.1k $3.8m $3.8m 0.63% New
30 GOLDMAN SACHS GROUP INC 0.00% of their portfolio NEW YORK, NY 149,216149.2k $5.0m $5.0m 0.00% Added +122.0k +122,029
31 NORTHERN TRUST CORP 0.00% of their portfolio CHICAGO, IL 125,933125.9k $4.2m $4.2m 0.00% Added +92.8k +92,767
32 Qube Research & Technologies Ltd 0.00% of their portfolio LONDON, X0 106,610106.6k $3.5m $3.5m 0.00% New
33 VANGUARD FIDUCIARY TRUST CO 0.00% of their portfolio MALVERN, PA 104,232104.2k $3.5m $3.5m 0.00% Added +9.4k +9,394
34 CITADEL ADVISORS LLC 0.00% of their portfolio MIAMI, FL 101,965102.0k $3.4m $3.4m 0.00% Reduced -15.6k -15,572
35 MACKENZIE FINANCIAL CORP 0.00% of their portfolio TORONTO ONTARIO, A6 94,76794.8k $3.1m $3.1m 0.00% New
36 RENAISSANCE TECHNOLOGIES LLC 0.00% of their portfolio NEW YORK, NY 86,32486.3k $2.9m $2.9m 0.00% Reduced -11.5k -11,500
37 Invesco Ltd. 0.00% of their portfolio ATLANTA, GA 57,30557.3k $1.9m $1.9m 0.00% Added +40.1k +40,140
38 Y-Intercept (Hong Kong) Ltd 0.04% of their portfolio HONG KONG, K3 55,87955.9k $1.9m $1.9m 0.04% New
39 Squarepoint Ops LLC 0.00% of their portfolio NEW YORK, NY 55,53955.5k $1.8m $1.8m 0.00% New
40 XTX Topco Ltd 0.02% of their portfolio LONDON, X0 52,16952.2k $1.7m $1.7m 0.02% Added +44.0k +43,966
41 CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.00% of their portfolio SAN FRANCISCO, CA 49,30249.3k $1.6m $1.6m 0.00% Added +38.7k +38,725
42 Sigma Planning Corp 0.04% of their portfolio ANN ARBOR, MI 45,02045.0k $1.5m $1.5m 0.04% Added +32.5k +32,500
43 Bank of New York Mellon Corp 0.00% of their portfolio NEW YORK, NY 41,36941.4k $1.4m $1.4m 0.00% New
44 BARCLAYS PLC 0.00% of their portfolio LONDON, X0 36,95437.0k $1.2m $1.2m 0.00% Added +36.8k +36,815
45 BANK OF AMERICA CORP /DE/ 0.00% of their portfolio CHARLOTTE, NC 36,14036.1k $1.2m $1.2m 0.00% Added +17.3k +17,267
46 Fisher Asset Management, LLC 0.00% of their portfolio PLANO, TX 35,29535.3k $1.2m $1.2m 0.00% Unchanged
47 Elmind Capital, LP 0.27% of their portfolio NEW YORK, NY 32,03732.0k $1.1m $1.1m 0.27% New
48 D. E. Shaw & Co., Inc. 0.00% of their portfolio New York, NY 30,12830.1k $1.0m $1.0m 0.00% New
49 Trexquant Investment LP 0.01% of their portfolio STAMFORD, CT 27,63627.6k $917.5k $917.5k 0.01% Reduced -6.7k -6,707
50 BNP PARIBAS FINANCIAL MARKETS 0.00% of their portfolio PARIS, I0 27,38327.4k $909.1k $909.1k 0.00% Added +27.3k +27,272
51 RHUMBLINE ADVISERS 0.00% of their portfolio BOSTON, MA 20,62820.6k $684.8k $684.8k 0.00% New
52 GSA CAPITAL PARTNERS LLP 0.04% of their portfolio LONDON, X0 19,74919.7k $656.0k $656.0k 0.04% Reduced -6.1k -6,073
53 SEI INVESTMENTS CO 0.00% of their portfolio OAKS, PA 16,38716.4k $544.0k $544.0k 0.00% New
54 Informed Momentum Co LLC 0.05% of their portfolio SOLANA BEACH, CA 16,23216.2k $538.9k $538.9k 0.05% New
55 DEUTSCHE BANK AG\ 0.00% of their portfolio FRANKFURT AM MAIN, 2M 15,56315.6k $516.7k $516.7k 0.00% New
56 RBF Capital, LLC 0.02% of their portfolio RENO, NV 15,27215.3k $507.0k $507.0k 0.02% Unchanged
57 PRICE T ROWE ASSOCIATES INC /MD/ 0.00% of their portfolio BALTIMORE, MD 13,59713.6k $452.0k $452.0k 0.00% New
58 WELLS FARGO & COMPANY/MN 0.00% of their portfolio SAN FRANCISCO, CA 13,54413.5k $449.7k $449.7k 0.00% New
59 MORGAN STANLEY 0.00% of their portfolio NEW YORK, NY 12,35612.4k $410.2k $410.2k 0.00% Added +1.8k +1,827
60 WELLINGTON MANAGEMENT GROUP LLP 0.00% of their portfolio Boston, MA 10,80010.8k $358.6k $358.6k 0.00% New
61 MetLife Investment Management, LLC 0.00% of their portfolio Whippany, NJ 9,4019.4k $312.1k $312.1k 0.00% New
62 Walleye Capital LLC 0.00% of their portfolio NEW YORK, NY 9,3069.3k $309.0k $309.0k 0.00% New
63 Integrated Quantitative Investments LLC 0.05% of their portfolio BELLEVUE, WA 8,9398.9k $296.8k $296.8k 0.05% New
64 SUSQUEHANNA INTERNATIONAL GROUP, LLP 0.00% of their portfolio BALA CYNWYD, PA 8,4268.4k $279.7k $279.7k 0.00% Reduced -76.5k -76,476
65 Lighthouse Investment Partners, LLC 0.01% of their portfolio Palm Beach Gardens, FL 8,3688.4k $277.8k $277.8k 0.01% New
66 CITIGROUP INC 0.00% of their portfolio NEW YORK, NY 7,4567.5k $247.5k $247.5k 0.00% Reduced -11.4k -11,389
67 MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. 0.00% of their portfolio CAUSEWAY BAY, K3 7,3137.3k $242.8k $242.8k 0.00% New
68 ALLIANCEBERNSTEIN L.P. 0.00% of their portfolio NASHVILLE, TN 7,3007.3k $242.4k $242.4k 0.00% New
69 STATE BOARD OF ADMINISTRATION OF FLORIDA RETIREMENT SYSTEM 0.00% of their portfolio TALLAHASSEE, FL 7,0017.0k $232.4k $232.4k 0.00% New
70 Persistent Asset Partners Ltd 0.07% of their portfolio HONG KONG, K3 6,5696.6k $218.1k $218.1k 0.07% Reduced -842 -842
71 Verdad Advisers, LP 0.20% of their portfolio BOSTON, MA 6,4006.4k $212.5k $212.5k 0.20% New
72 HSBC HOLDINGS PLC 0.00% of their portfolio LONDON, X0 6,2346.2k $205.7k $205.7k 0.00% New
73 NEW YORK STATE COMMON RETIREMENT FUND 0.00% of their portfolio ALBANY, NY 5,6005.6k $185.9k $185.9k 0.00% New
74 Vanguard Global Advisers, LLC 0.00% of their portfolio MALVERN, PA 5,4455.4k $180.8k $180.8k 0.00% Reduced -1.7k -1,737
75 Police & Firemen's Retirement System of New Jersey 0.00% of their portfolio TRENTON, NJ 4,7044.7k $156.2k $156.2k 0.00% New
76 Legal & General Group Plc 0.00% of their portfolio London, X0 3,4623.5k $114.9k $114.9k 0.00% New
77 State of Wyoming 0.01% of their portfolio CHEYENNE, WY 1,6181.6k $53.7k $53.7k 0.01% New
78 Ameritas Investment Partners, Inc. 0.00% of their portfolio LINCOLN, NE 1,4481.4k $48.1k $48.1k 0.00% New
79 FMR LLC 0.00% of their portfolio BOSTON, MA 1,3391.3k $44.5k $44.5k 0.00% Added +289 +289
80 Russell Investments Group, Ltd. 0.00% of their portfolio Seattle, WA 1,2751.3k $42.3k $42.3k 0.00% New
81 FNY Investment Advisers, LLC 0.01% of their portfolio NEW YORK, NY 1,0001.0k $33.0k $33.0k 0.01% Unchanged
82 Tower Research Capital LLC (TRC) 0.00% of their portfolio NEW YORK, NY 866866 $28.8k $28.8k 0.00% New
83 ROYAL BANK OF CANADA 0.00% of their portfolio TORONTO, A6 687687 $23.0k $23.0k 0.00% Added +675 +675
84 Owl Creek Wealth Partners LLC 0.00% of their portfolio DENVER, CO 491491 $16.3k $16.3k 0.00% Unchanged
85 Sterling Capital Management LLC 0.00% of their portfolio CHARLOTTE, NC 281281 $9.3k $9.3k 0.00% New
86 CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 0.00% of their portfolio WEST SACRAMENTO, CA 220220 $7.3k $7.3k 0.00% New
87 Quantbot Technologies LP 0.00% of their portfolio NEW YORK, NY 201201 $6.7k $6.7k 0.00% New
88 Physician Wealth Advisors, Inc. 0.00% of their portfolio MIDVALE, UT 182182 $6.0k $6.0k 0.00% Unchanged
89 OSAIC HOLDINGS, INC. 0.00% of their portfolio SCOTTSDALE, AZ 100100 $3.3k $3.3k 0.00% Reduced -1.2k -1,180
90 PNC Financial Services Group, Inc. 0.00% of their portfolio Pittsburgh, PA 6262 $2.1k $2.1k 0.00% Unchanged
91 Avion Wealth 0.00% of their portfolio THE WOODLANDS, TX 4646 $1.0k $1.0k 0.00% Reduced -26 -26
92 NISA INVESTMENT ADVISORS, LLC 0.00% of their portfolio ST. LOUIS, MO 4444 $1.5k $1.5k 0.00% Unchanged
93 HighMark Wealth Management LLC 0.00% of their portfolio ST. PAUL, MN 2323 $763 $763 0.00% Unchanged
94 Arax Advisory Partners 0.00% of their portfolio NEW YORK, NY 1616 $531 $531 0.00% Reduced -25 -25
95 FIFTH THIRD BANCORP 0.00% of their portfolio CINCINNATI, OH 22 $66 $66 0.00% Unchanged
96 Steward Partners Investment Advisory, LLC 0.00% of their portfolio STAMFORD, CT 22 $66 $66 0.00% New
97 Optiver Holding B.V. 0.00% of their portfolio AMSTERDAM, P7 22 $66 $66 0.00% New