AI Holders Summary · Q1 2026

126 institutions reported SION in Q1 2026. RA CAPITAL MANAGEMENT, L.P. leads at 24.7% of the visible book.

Top holders

Sorted by position value. Source: SEC EDGAR 13F-HR filings.

Hide index funds / market makers / custodians(2 on this page)

#HolderValueShares% port.Quarter

RA CAPITAL MANAGEMENT, L.P.

CIK 0001346824

$397M9.9M4.21%Q1 2026 02

TPG GP A, LLC

CIK 0001903793

$260M6.5M7.08%Q1 2026 03

ORBIMED ADVISORS LLC

CIK 0001055951

$142M3.5M2.82%Q1 2026 04

VIKING GLOBAL INVESTORS LP

CIK 0001103804

$128M3.2M0.36%Q1 2026 05

Atlas Venture Life Science Advisors, LLC

CIK 0001917529

$120M3.0M15.20%Q1 2026 06

Enavate Sciences GP, LLC

CIK 0001953107

$99M2.5M28.26%Q1 2026 07

JPMORGAN CHASE & CO

CIK 0000019617

$54M1.5M0.00%Q1 2026 08

BlackRock, Inc.

CIK 0002012383

$52M1.3M0.00%Q1 2026 09

JENNISON ASSOCIATES LLC

CIK 0000053417

$46M1.1M0.03%Q4 2025 10

CITADEL ADVISORS LLC

CIK 0001423053

$45M1.1M0.01%Q4 2025 11

VANGUARD CAPITAL MANAGEMENT LLC

CIK 0002100119· Index

$41M1.0M0.00%Q1 2026 12

DEERFIELD MANAGEMENT COMPANY, L.P.

CIK 0001009258

$40M971K0.51%Q4 2025 13

PRICE T ROWE ASSOCIATES INC /MD/

CIK 0000080255

$30M756K0.00%Q1 2026 14

STATE STREET CORP

CIK 0000093751

$30M756K0.00%Q1 2026 15

PERCEPTIVE ADVISORS LLC

CIK 0001224962

$26M658K0.52%Q1 2026 16

EVENTIDE ASSET MANAGEMENT, LLC

CIK 0001442891

$26M646K0.43%Q1 2026 17

Aberdeen Group plc

CIK 0001716774

$23M564K0.04%Q1 2026 18

BAKER BROS. ADVISORS LP

CIK 0001263508

$16M400K0.10%Q4 2025 19

Kalehua Capital Management LLC

CIK 0002106181

$16M394K6.08%Q1 2026 20

GEODE CAPITAL MANAGEMENT, LLC

CIK 0001214717· Index

$16M390K0.00%Q1 2026

Page 1 of 7

106 more holders available. Log in →