993 hedge funds and large institutions have $24.6B invested in Biogen in 2026 Q1 according to their latest regulatory filings, with 133 funds opening new positions, 395 increasing their positions, 287 reducing their positions, and 107 closing their positions.

New
Increased
Maintained
Reduced
Closed

more repeat investments, than reductions

Existing positions increased: | Existing positions reduced:

more first-time investments, than exits

New positions opened: | Existing positions closed:

more capital invested

Capital invested by funds: $ → $

more funds holding

Funds holding:

10% less call options, than puts

Call options by funds: $324M | Put options by funds: $360M

3.8% less ownership

Funds ownership: 95.26%91.46% (-3.8%)

13% less funds holding in top 10

Funds holding in top 10: 87 (-1)

Holders
993
Holders Change
Holders Change %
% of All Funds
Holding in Top 10
7
Holding in Top 10 Change
Holding in Top 10 Change %
% of All Funds
New
Increased
Reduced
Closed
Calls
$324M
Puts
$360M
Net Calls
Net Calls Change
Name Holding Trade Value Shares
Change
Change in
Stake
AllianceBernstein
76
AllianceBernstein
Tennessee
$37.5M
Renaissance Technologies
77
Renaissance Technologies
New York
$37.3M
Hudson Bay Capital Management
78
Hudson Bay Capital Management
Connecticut
$36.9M
LGM
79
Logos Global Management
California
$36.7M
KK
80
KLP Kapitalforvaltning
Norway
$36.5M
SG Americas Securities
81
SG Americas Securities
New York
$35.9M
Principal Financial Group
82
Principal Financial Group
Iowa
$34.3M
Allianz Asset Management
83
Allianz Asset Management
Germany
$32.6M
Prudential Financial
84
Prudential Financial
New Jersey
$30M
IC
85
IEQ Capital
California
$27.9M
ECM
86
ExodusPoint Capital Management
New York
$27.9M
Aberdeen Group
87
Aberdeen Group
United Kingdom
$27.7M
LBA
88
Letko, Brosseau & Associates
Quebec, Canada
$27.7M
Franklin Resources
89
Franklin Resources
California
$26.5M
PAM
90
Panagora Asset Management
Massachusetts
$26M
OSAM
91
O'Shaughnessy Asset Management
Connecticut
$25.9M
PAI
92
Palo Alto Investors
California
$25.8M
Susquehanna International Group
93
Susquehanna International Group
Pennsylvania
$25.7M
Citadel Advisors
94
Citadel Advisors
Florida
$25.3M
Russell Investments Group
95
Russell Investments Group
United Kingdom
$25.1M
Ameriprise
96
Ameriprise
Minnesota
$24.3M
ECSS
97
Eurizon Capital SGR SpA
$23.7M
TD Asset Management
98
TD Asset Management
Ontario, Canada
$23.3M
Wells Fargo
99
Wells Fargo
California
$23.3M
State Board of Administration of Florida Retirement System
100
State Board of Administration of Florida Retirement System
Florida
$22.8M