13F

Stock

Upstream Bio, Inc.

UPB · held by 134 managers

Reported value

$1.39B

Holders

134

+2 new · −0 exited

Holders’ est. mark

$22.3M

Price effect on 7 books still in the name

Largest holder

$204.1M

Fidelity

Notable conviction

Share of each notable manager’s 13F book.

Holder count by quarter

Who holds it

Notable only
InvestorSharesValueEst. markChange
Fidelity7.52M$204.1M—Held
ORBIMED ADVISORS LLC5.69M$154.6M—Held
BlackRock, Inc.3.34M$90.8M—Held
Decheng Capital LLC3.14M$85.3M—Held
NORGES BANK2.88M$78.3M$20.4MAdded$72.3M
ENAVATE SCIENCES GP, LLC2.46M$66.8M—Held
Vanguard2.39M$64.8M—Held
UBS Group AG1.81M$49M—Held
JANUS HENDERSON GROUP PLC1.53M$41.4M—Held
Altshuler Shaham Ltd1.34M$36.4M—Held
Bain Capital Life Sciences Investors, LLC1.33M$36.1M—Held
Omega Fund Management, LLC1.33M$36M—Held
State Street1.32M$35.8M—Held
VR ADVISER, LLC1.17M$31.7M—Held
WELLINGTON MANAGEMENT GROUP LLP894.7K$24.3M—Held
GEODE CAPITAL MANAGEMENT, LLC851.9K$23.1M—Held
Parkman Healthcare Partners LLC834.6K$22.7M—Held
Pictet Asset Management Holding SA773.1K$21M—Held
Woodline Partners LP760.3K$20.6M—Held
Integral Health Asset Management, LLC750K$20.4M—Held
TCG Crossover Management, LLC743.9K$20.2M—Held
SAMSARA BIOCAPITAL, LLC736K$20M—Held
Vestal Point Capital, LP720K$19.5M—Held
Siren, L.L.C.588.5K$16M—Held
BARCLAYS PLC524.5K$14.2M$711.5KAdded$12.6M
MILLENNIUM MANAGEMENT LLC517.3K$14M—Held
Nantahala Capital Management, LLC495K$13.4M—Held
MARSHALL WACE, LLP343.8K$9.33M—Held
GOLDMAN SACHS GROUP INC333.5K$9.05M—Held
GREAT POINT PARTNERS LLC300K$8.14M—Held
Alyeska Investment Group, L.P.298.3K$8.1M—Held
JENNISON ASSOCIATES LLC288.8K$7.84M—Held
CHARLES SCHWAB INVESTMENT MANAGEMENT INC284.9K$7.74M—Held
NORTHERN TRUST CORP236.8K$6.43M—Held
Squadron Capital Management LLC230.7K$6.26M—Held
Invesco Ltd.163.2K$4.43M—Held
Boxer Capital Management, LLC150K$4.07M—New
DEUTSCHE BANK AG\127.8K$3.47M—Held
MORGAN STANLEY122.1K$3.31M$730KAdded$1.67M
SummitTX Capital, L.P.116.7K$3.17M—Held
Schonfeld Strategic Advisors LLC115.8K$3.14M—Held
JPMORGAN CHASE & CO110.3K$2.99M—Held
AMERICAN CENTURY COMPANIES INC87.8K$2.38M—Held
BANK OF AMERICA CORP /DE/86.4K$2.35M$462.6KAdded$1.3M
Bank of New York Mellon Corp84.9K$2.3M—Held
Nuveen, LLC78.6K$2.13M—Held
ExodusPoint Capital Management, LP75.4K$2.05M—Held
Artia Global Partners LP68.7K$1.86M—Held
Exome Asset Management LLC64.8K$1.76M—Held
AMERIPRISE FINANCIAL INC56.6K$1.54M—Held
SUSQUEHANNA INTERNATIONAL GROUP, LLP55.8K$1.52M—Held
SEVEN GRAND MANAGERS, LLC50K$1.36M—Held
Y-Intercept (Hong Kong) Ltd46.6K$1.26M—Held
ALPS ADVISORS INC44.4K$1.2M—Held
RHUMBLINE ADVISERS41.5K$1.13M—Held
Rafferty Asset Management, LLC38.7K$1.05M—Held
WELLS FARGO & COMPANY/MN36.8K$999K—Held
Trexquant Investment LP31K$843K—Held
ALLIANCEBERNSTEIN L.P.31K$841.9K—Held
Icahn Capital30.5K$828.2K—Held
D. E. Shaw & Co., Inc.27.1K$735.5K—Held
Swiss National Bank26.6K$722.2K—Held
DIADEMA PARTNERS LP20.5K$556.6K—Held
MetLife Investment Management, LLC19.7K$534.3K—Held
PSP Research LLC17.6K$478.8K—Held
MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd.17.5K$475.3K—Held
PRELUDE CAPITAL MANAGEMENT, LLC16.6K$449.6K—Held
Renaissance Technologies16.4K$445.3K—Held
Quantinno Capital Management LP15.4K$418.5K—Held
XTX Topco Ltd15.1K$409.7K—Held
CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM14.7K$397.8K—Held
PROFUND ADVISORS LLC14.6K$395.9K—Held
Graham Capital Management, L.P.13.7K$372.3K—Held
Legal & General Group Plc13.7K$372.2K—Held
Citadel13.4K$364.4K—Held
DNB Asset Management AS12.8K$347.3K—Held
Verition Fund Management LLC12K$326.3K—Held
Mariner, LLC11.8K$321.2K—Held
Creative Planning11.7K$319K—Held
NEW YORK STATE COMMON RETIREMENT FUND11.7K$317.7K—Held
TWO SIGMA INVESTMENTS, LP10.5K$285.1K—Held
INTECH INVESTMENT MANAGEMENT LLC10.4K$282.3K—Held
MANUFACTURERS LIFE INSURANCE COMPANY, THE10.1K$275.5K—Held
Virtus Investment Advisers, LLC9.8K$266.1K—Held
STRS OHIO9.8K$266.1K—Held
VARCOV Co.9.62K$261.2K—Held
Police & Firemen's Retirement System of New Jersey9.46K$256.7K—Held
Persistent Asset Partners Ltd8.91K$241.8K—New
China Universal Asset Management Co., Ltd.8.81K$239.1K—Held
ProShare Advisors LLC8.35K$226.8K—Held
SEI INVESTMENTS CO8.09K$219.6K—Held
CITIGROUP INC6.95K$188.7K—Held
BNP PARIBAS FINANCIAL MARKETS4.98K$135.1K—Held
KLP KAPITALFORVALTNING AS2.9K$78.7K—Held
Russell Investments Group, Ltd.2.82K$76.6K—Held
Ameritas Investment Partners, Inc.2.74K$74.4K—Held
Mirae Asset Global Investments Co., Ltd.2.63K$71.3K—Held
Wellington Grp LLC2K$54.3K—Held
Sterling Capital Management LLC1.92K$52.1K—Held
Torren Management, LLC1.1K$29.8K—Held
GF FUND MANAGEMENT CO. LTD.1.06K$28.8K—Held
ROYAL BANK OF CANADA969$26K—Held
GAMMA Investing LLC900$24.4K—Held
Tower Research Capital LLC (TRC)669$18.2K—Held
Versant Capital Management, Inc558$15.2K—Held
US BANCORP \DE\546$14.8K—Held
FEDERATED HERMES, INC.482$13.1K—Held
SIMPLEX TRADING, LLC466$12.7K—Held
NISA INVESTMENT ADVISORS, LLC400$10.9K—Held
EverSource Wealth Advisors, LLC282$7.66K—Held
Global Retirement Partners, LLC273$7.41K—Held
Aster Capital Management (DIFC) Ltd271$7.36K—Held
UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC242$6.57K—Held
J.Safra Asset Management Corp128$3.48K—Held
SIGNATUREFD, LLC117$3.18K—Held
PNC Financial Services Group, Inc.106$2.88K—Held
Essential Partners LLC97$2.63K$809Added$809
Allworth Financial LP68$1.85K$559Added$586
N.E.W. Advisory Services LLC60$1.63K—Held
SageView Advisory Group, LLC30$815—Held
PRICE T ROWE ASSOCIATES INC /MD/19.6K$534—Held
Sunbelt Securities, Inc.19$516—Held
Larson Financial Group LLC14$380—Held
Virtu Financial LLC12.2K$332—Held
SG Americas Securities, LLC5.52K$150—Held
OSAIC HOLDINGS, INC.5$136—Held
CWM, LLC3.36K$91—Held
Parallel Advisors, LLC2$54—Held
Arax Advisory Partners2$54—Held
AMALGAMATED BANK1.03K$28—Held
ROTHSCHILD INVESTMENT LLC1$27—Held
IFP Advisors, Inc1$27$8Cut−$11
Daiwa Securities Group Inc.180$5—Held
NOMURA ASSET MANAGEMENT CO LTD0$0—Held

Positions as of Q4 2025. 13F filings arrive up to 45 days after quarter-end and omit shorts. Values are quarter-end marks, as filed. Estimated mark is the price effect on shares still held — not realized P&L or investment advice.