UPB · Upstream Bio, Inc. · Holdings

$5.73 -0.02 (-0.35%) At close · Sep 11

Russell 2000 member Rebalance outlook locked

Market Cap

$313.84M

54.77M

Institutional ownership from SEC Form 13F filings. Investment managers with more than $100 million in U.S. equities must disclose their positions every quarter, within 45 days of quarter-end, so the holdings shown can lag the market by up to a quarter.

Use institutional holdings through the 13F API or MCP →

Quarter:

Holders: 150

Total Value: $350,208,829

Total Shares: 50,608,226

Showing 1–100 of 151 holdings by value · page 1 of 2

Institutional Ownership Trend

7 quarters

Holder Concentration

Across 150 13F filers · Δ vs Mar 31, 2026

Top Holder

16.1%

−1.9 pts

Top 5

47.6%

−2.0 pts

Top 10

62.5%

+0.1 pts

HHI

614

Broadly held−70

Quarterly Activity

vs Mar 31, 2026

New

Increased

Decreased

Sold Out

Unchanged

Holder count: +7

Institutional value: -13.6%

Shares held: +12.4%

Top Buyers

vs Mar 31, 2026

Institution	Added	Now Holds
Mega JPMORGAN CHASE & CO	+549,043	1,012,044
Mega AQR CAPITAL MANAGEMENT LLC	+472,698	544,869
Mega BNP PARIBAS ARBITRAGE, SA	+385,546	511,546
Mega BlackRock, Inc.	+382,669	3,753,358
Mega Qube Research & Technologies Ltd	+359,179	978,500

Top Sellers

vs Mar 31, 2026

Institution	Sold	Now Holds
Mega HSBC HOLDINGS PLC	−629,533	10,793
Mid SAMSARA BIOCAPITAL, LLC	−382,330	353,717
Mid Y-Intercept (Hong Kong) Ltd	−307,076	693,555
Mid Bain Capital Life Sciences Investors, LLC	−266,262	600,949
Small SPHERA FUNDS MANAGEMENT LTD.	−138,300	219,700

Top New Positions

vs Mar 31, 2026

Institution	Acquired	Value (USD)
Mega NORGES BANK	3,768,619	$26,078,843
Large Walleye Capital LLC	498,490	$3,449,550
Mid Voleon Capital Management LP	285,234	$1,973,819
Large JACOBS LEVY EQUITY MANAGEMENT, INC	253,092	$1,751,396
Large ACADIAN ASSET MANAGEMENT LLC	175,110	$1,211,761

Top Sold-Out Positions

vs Mar 31, 2026

Institution	Previously Held	Last Value (USD)
Large FEDERATED HERMES, INC.	979,758	$8,817,822
Mega Pictet Asset Management Holding SA	733,431	$6,600,879
Mid Nantahala Capital Management, LLC	400,000	$3,600,000
Large Alyeska Investment Group, L.P.	298,329	$2,684,961
Small Prosight Management, LP	241,123	$2,170,107

Filter: New 36 Increased 66 Reduced 30 Sold out 29 Unchanged 18

Showing 100 of 151

All Common Calls Puts

Compact Export CSV

Holder

Value (USD)

% of 13F

FMR LLC

$56,487,246

16.13%

8,162,897

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Fidelity Management & Research Co LLC	7,271,423	$50,318,247	89.1%	Defined
Fidelity Institutional Asset Management Trust Co	727,357	$5,033,310	8.9%	Defined
FIAM LLC	164,117	$1,135,689	2.0%	Defined

ORBIMED ADVISORS LLC

$39,399,635

11.25%

5,693,589

NORGES BANK

$26,078,843

7.45%

3,768,619

BlackRock, Inc.

$25,973,232

7.42%

3,753,358

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
BLACKROCK FINANCIAL MANAGEMENT INC/DE	152,431	$1,054,822	4.1%	Sole
BlackRock Asset Management Canada Ltd	321	$2,221	0.0%	Sole
BlackRock Investment Management, LLC	109,776	$759,649	2.9%	Sole
BLACKROCK ADVISORS LLC	495,363	$3,427,911	13.2%	Sole
BlackRock Fund Advisors	1,604,714	$11,104,620	42.8%	Sole
BlackRock Institutional Trust Company, N.A.	1,040,400	$7,199,568	27.7%	Sole
BlackRock Japan Co. Ltd	2,249	$15,563	0.1%	Sole
BlackRock Fund Managers Ltd.	9,279	$64,210	0.2%	Sole
BlackRock Investment Management (UK) Ltd.	22,412	$155,091	0.6%	Sole
BlackRock Asset Management Ireland Ltd	44,459	$307,656	1.2%	Sole
BlackRock (Luxembourg) S.A.	234,134	$1,620,207	6.2%	Sole
Aperio Group, LLC	37,820	$261,714	1.0%	Sole

Decheng Capital LLC

$18,856,086

5.38%

2,724,868

ENAVATE SCIENCES GP, LLC

$17,021,144

4.86%

2,459,703

VANGUARD CAPITAL MANAGEMENT LLC

$12,986,999

3.71%

1,876,734

MILLENNIUM MANAGEMENT LLC

$7,914,923

2.26%

1,143,775

D. E. Shaw & Co., Inc.

$7,169,423

2.05%

1,036,044

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
D. E. SHAW & CO, L.P.	837,568	$5,795,970	80.8%	Defined
D. E. Shaw Investment Management, L.L.C. joint	198,476	$1,373,453	19.2%	Defined

JPMORGAN CHASE & CO

$7,003,343

2.00%

1,012,044

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
JPMorgan Chase Bank, N.A.	18,166	$125,708	1.8%	Defined
J.P. Morgan Investment Management Inc.	72,885	$504,364	7.2%	Defined
J.P. Morgan Securities LLC	916,682	$6,343,439	90.6%	Defined
J.P. Morgan Securities plc	4,311	$29,832	0.4%	Defined

Qube Research & Technologies Ltd

$6,771,220

1.93%

978,500

Parkman Healthcare Partners LLC

$6,471,909

1.85%

935,247

GEODE CAPITAL MANAGEMENT, LLC

$6,444,325

1.84%

931,261

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
GEODE CAPITAL MANAGEMENT TRUST COMPANY, LLC	130,972	$906,326	14.1%	Defined
Held directly	800,289	$5,537,999	85.9%	Defined

SEB Asset Management AB

$6,079,033

1.74%

878,473

Woodline Partners LP

$5,753,848

1.64%

831,481

STATE STREET CORP

$5,302,955

1.51%

766,323

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
STATE STREET GLOBAL ADVISORS EUROPE LIMITED joint	766,323	$5,302,955	100.0%	Defined

VANGUARD PORTFOLIO MANAGEMENT LLC

$4,931,655

1.41%

712,667

Y-Intercept (Hong Kong) Ltd

$4,799,400

1.37%

693,555

Bain Capital Life Sciences Investors, LLC

$4,158,567

1.19%

600,949

AQR CAPITAL MANAGEMENT LLC

$3,770,491

1.08%

544,869

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
RF&L WEALTH MANAGEMENT, LLC	23	$159	0.0%	Other
Compound Planning, Inc.	8	$55	0.0%	Other
Arax Advisory Partners	1,709	$11,826	0.3%	Other
HALBERT HARGROVE GLOBAL ADVISORS, LLC	1,070	$7,404	0.2%	Other
Stokes Family Office, LLC	854	$5,909	0.2%	Other
Held directly	541,205	$3,745,138	99.3%	Defined

MORGAN STANLEY

$3,630,451

1.04%

524,632

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
MORGAN STANLEY & CO INTERNATIONAL PLC	5,258	$36,385	1.0%	Defined
MORGAN STANLEY & CO. LLC	9,972	$69,006	1.9%	Defined
MORGAN STANLEY CAPITAL SERVICES, LLC	462,064	$3,197,482	88.1%	Defined
MORGAN STANLEY SMITH BARNEY LLC	2,110	$14,601	0.4%	Defined
PARAMETRIC PORTFOLIO ASSOCIATES LLC	45,228	$312,977	8.6%	Defined

BNP PARIBAS ARBITRAGE, SA

$3,539,898

1.01%

511,546

Walleye Capital LLC

$3,449,550

0.98%

498,490

Trexquant Investment LP

$3,227,695

0.92%

466,430

Point72 Asset Management, L.P.

$3,134,836

0.90%

453,011

BANK OF AMERICA CORP /DE/

$2,710,993

0.77%

391,762

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
BANK OF AMERICA NA	391,762	$2,710,993	100.0%	Defined

DIMENSIONAL FUND ADVISORS LP

$2,640,761

0.75%

381,613

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Dimensional Fund Advisors Ltd.	4,862	$33,645	1.3%	Defined
DFA Australia Ltd.	7,036	$48,689	1.8%	Defined
Dimensional Ireland Ltd	28,174	$194,964	7.4%	Defined
Held directly	341,541	$2,363,463	89.5%	Sole

Altshuler Shaham Ltd

$2,630,022

0.75%

380,061

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Altshuler Shaham Provident & Pension Funds Ltd.	380,061	$2,630,022	100.0%	Defined

ARROWSTREET CAPITAL, LIMITED PARTNERSHIP

$2,475,671

0.71%

357,756

SAMSARA BIOCAPITAL, LLC

$2,447,721

0.70%

353,717

Propel Bio Management, LLC

$2,424,691

0.69%

350,389

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Simplify Asset Management Inc.	350,389	$2,424,691	100.0%	Defined

WELLINGTON MANAGEMENT GROUP LLP

$2,369,082

0.68%

342,353

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Wellington Management Company LLP	342,353	$2,369,082	100.0%	Defined

NORTHERN TRUST CORP

$2,057,632

0.59%

297,346

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
NORTHERN TRUST CO joint	277,528	$1,920,493	93.3%	Defined
NORTHERN TRUST GLOBAL INVESTMENTS LTD	14,304	$98,983	4.8%	Defined
DWS INVESTMENT MANAGEMENT AMERICAS, INC joint	5,514	$38,156	1.9%	Other

Squarepoint Ops LLC

$2,013,055

0.57%

290,904

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Squarepoint Capital LLP	290,904	$2,013,055	100.0%	Defined

Voleon Capital Management LP

$1,973,819

0.56%

285,234

CHARLES SCHWAB INVESTMENT MANAGEMENT INC

$1,816,195

0.52%

262,456

JACOBS LEVY EQUITY MANAGEMENT, INC

$1,751,396

0.50%

253,092

GOLDMAN SACHS GROUP INC

$1,708,665

0.49%

246,917

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
GOLDMAN SACHS & CO. LLC	246,917	$1,708,665	100.0%	Defined

XTX Topco Ltd

$1,677,034

0.48%

242,346

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
XTX EXECUTION SERVICES LLC joint	242,346	$1,677,034	100.0%	Defined

DEUTSCHE BANK AG\

$1,670,812

0.48%

241,447

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
DWS Investment GmbH	208,418	$1,442,252	86.3%	Defined
DWS Investments UK Ltd	33,029	$228,560	13.7%	Defined

VANGUARD FIDUCIARY TRUST CO

$1,658,142

0.47%

239,616

UBS Group AG

$1,624,220

0.46%

234,714

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
UBS AG	234,711	$1,624,200	100.0%	Defined
UBS Securities LLC	3	$20	0.0%	Defined

Schonfeld Strategic Advisors LLC

$1,562,259

0.45%

225,760

Jump Financial, LLC

$1,544,702

0.44%

223,223

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Jump Trading Holdings, LLC	259	$1,792	0.1%	Defined
Leap GP LLC joint	222,964	$1,542,910	99.9%	Defined

SPHERA FUNDS MANAGEMENT LTD.

$1,520,324

0.43%

219,700

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Sphera Global Healthcare Management LP joint	219,700	$1,520,324	100.0%	Defined

ACADIAN ASSET MANAGEMENT LLC

$1,211,761

0.35%

175,110

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Acadian Inc	175,110	$1,211,761	100.0%	Defined

HRT FINANCIAL LP

$1,180,482

0.34%

170,590

Boxer Capital Management, LLC

$1,038,000

0.30%

150,000

RENAISSANCE TECHNOLOGIES LLC

$908,596

0.26%

131,300

EntryPoint Capital, LLC

$895,766

0.26%

129,446

ALGERT GLOBAL LLC

$820,919

0.23%

118,630

Bank of New York Mellon Corp

$593,368

0.17%

85,747

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Mellon Investments Corporation	28,571	$197,711	33.3%	Defined
The Bank of New York Mellon	56,356	$389,983	65.7%	Defined
BNY Mellon, NA joint	820	$5,674	1.0%	Defined

Nuveen, LLC

$586,608

0.17%

84,770

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Nuveen Asset Management, LLC joint	8,087	$55,962	9.5%	Defined
TEACHERS ADVISORS, LLC joint	76,683	$530,646	90.5%	Defined

AMERICAN CENTURY COMPANIES INC

$541,102

0.15%

78,194

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
AMERICAN CENTURY INVESTMENT MANAGEMENT INC	78,194	$541,102	100.0%	Defined

Man Group plc

$510,855

0.15%

73,823

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Numeric Investors LLC	73,823	$510,855	100.0%	Defined

GSA CAPITAL PARTNERS LLP

$479,888

0.14%

69,348

Simplify Asset Management Inc.

$429,821

0.12%

62,113

ALPS ADVISORS INC

$382,177

0.11%

55,228

Quantinno Capital Management LP

$379,478

0.11%

54,838

Virtus Investment Advisers, LLC

$371,174

0.11%

53,638

Invesco Ltd.

$369,505

0.11%

53,397

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Invesco Advisers, Inc. joint	4,573	$31,644	8.6%	Defined
Invesco Trust Co joint	12,227	$84,610	22.9%	Defined
Invesco Capital Management LLC	36,597	$253,251	68.5%	Defined

ALLIANCEBERNSTEIN L.P.

$357,625

0.10%

51,680

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Equitable Holdings, Inc.	51,680	$357,625	100.0%	Defined

Brevan Howard Capital Management LP

$348,553

0.10%

50,369

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Brevan Howard US Investment Management, LP	50,369	$348,553	100.0%	Defined

Swiss National Bank

$332,852

0.10%

48,100

Russell Investments Group, Ltd.

$328,996

0.09%

47,543

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Russell Investment Management, LLC joint	28,112	$194,534	59.1%	Defined
Russell Investments Capital, LLC joint	11,507	$79,628	24.2%	Other
Russell Investments Trust Company joint	7,924	$54,834	16.7%	Other

Allspring Global Investments Holdings, LLC

$298,819

0.09%

43,182

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Allspring Global Investments, LLC reporting on behalf of UBS ASSET MANAGEMENT AMERICAS INC	43,182	$298,819	100.0%	Defined

RHUMBLINE ADVISERS

$293,297

0.08%

42,384

TWO SIGMA INVESTMENTS, LP

$292,889

0.08%

42,325

ExodusPoint Capital Management, LP

$284,031

0.08%

41,045

CITIGROUP INC

$279,145

0.08%

40,339

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Citigroup Financial Products Inc. joint	40,339	$279,145	100.0%	Defined

CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM

$267,347

0.08%

38,634

Stonepine Capital Management, LLC

$231,349

0.07%

33,432

Mariner, LLC

$229,335

0.07%

33,141

WELLS FARGO & COMPANY/MN

$204,119

0.06%

29,497

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
WELLS FARGO BANK N A	29,497	$204,119	100.0%	Defined

BARCLAYS PLC

$202,118

0.06%

29,208

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
BARCLAYS BANK PLC	27,978	$193,607	95.8%	Defined
BARCLAYS CAPITAL INC.	1,230	$8,511	4.2%	Defined

Creative Planning

$197,101

0.06%

28,483

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
CREATIVE PLANNING TRUST Co LLC	3,814	$26,392	13.4%	Defined
Held directly	24,669	$170,709	86.6%	Sole

Quantbot Technologies LP

$194,991

0.06%

28,178

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Manager 1	28,178	$194,991	100.0%	Sole

PRICE T ROWE ASSOCIATES INC /MD/

$194,161

0.06%

28,058

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
T. Rowe Price International Ltd	28,058	$194,161	100.0%	Defined

AXQ CAPITAL, LP

$187,310

0.05%

27,068

nVerses Capital, LLC

$166,280

0.05%

24,029

DNB Asset Management AS

$163,312

0.05%

23,600

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
DNB FUND	23,600	$163,312	100.0%	Other

VANGUARD ASSET MANAGEMENT, Ltd

$157,250

0.04%

22,724

Graham Capital Management, L.P.

$155,755

0.04%

22,508

LOS ANGELES CAPITAL MANAGEMENT LLC

$154,904

0.04%

22,385

Verdad Advisers, LP

$150,925

0.04%

21,810

MetLife Investment Management, LLC

$144,295

0.04%

20,852

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
METLIFE INC	20,852	$144,295	100.0%	Defined

SG Americas Securities, LLC

$140,738

0.04%

20,338

SEI INVESTMENTS CO

$138,579

0.04%

20,026

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
SEI TRUST CO	20,026	$138,579	100.0%	Sole

WINTON GROUP Ltd

$137,016

0.04%

19,800

IEQ CAPITAL, LLC

$135,182

0.04%

19,535

DIADEMA PARTNERS LP

$132,123

0.04%

19,093

Shay Capital LLC

$124,560

0.04%

18,000

Quadrature Capital Ltd

$124,476

0.04%

17,988

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Quadrature US Inc.	17,988	$124,476	100.0%	Other

Entropy Technologies, LP

$121,390

0.03%

17,542

STATE OF WISCONSIN INVESTMENT BOARD

$118,089

0.03%

17,065

MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd.

$112,221

0.03%

16,217

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Global X Management CO LLC joint	16,217	$112,221	100.0%	Defined

MANUFACTURERS LIFE INSURANCE COMPANY, THE

$108,886

0.03%

15,735

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
MANULIFE FINANCIAL CORP joint	15,735	$108,886	100.0%	Defined

JANE STREET GROUP, LLC

$107,910

0.03%

15,594

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Jane Street Capital, LLC	11,174	$77,324	71.7%	Defined
Jane Street Global Trading, LLC	4,420	$30,586	28.3%	Defined

CITADEL ADVISORS LLC

$103,800

0.03%

15,000

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Citadel Securities GP LLC	15,000	$103,800	100.0%	Defined

MERCER GLOBAL ADVISORS INC /ADV

$92,395

0.03%

13,352

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