BIOGEN INC (BIIB) Institutional Ownership Changes & 13F Activity

BIOGEN INC (BIIB) institutional ownership data tracks hedge funds, asset managers, and other institutional investors based on recent SEC 13F filings (Q2 2026). This page analyzes institutional buying and selling activity, new holdings, and sold-out positions among tracked filers. Notable filers include Sequoia Financial Advisors, Causeway Capital Management, Renaissance Technologies LLC, Hillman Value Fund, and Parnassus Endeavor Fund.

Portfolio quarterNameTypeQuantityRemainingReported stock balance
Q1 2022Longleaf PartnersSell-15,561842,962$177,528
Q1 2022Hillman Value FundBuy15,48842,679$8,988
Q1 2022Hancock Classic ValueSell-4732,384$502
Q4 2021Longleaf PartnersBuy254,633858,523$205,977
Q4 2021Renaissance Technologies LLCBuy92,1001,073,807$257,628
Q4 2021Hillman Value FundSell-1,09827,191$6,523
Q3 2021Renaissance Technologies LLCSell-348,296981,707$277,813
Q3 2021Hillman Value FundBuy1,05028,289$8,005
Q2 2021Renaissance Technologies LLCSell-608,1591,330,003$460,540
Q2 2021Parnassus Endeavor FundBuy137,641452,053$156,532
Q2 2021Miller Value PartnersBuy79,49379,493$27,526
Q2 2021Hillman Value FundSell-5027,239$9,432
Q2 2021Muhlenkamp & CoBuy3418,218$6,308
Q1 2021Renaissance Technologies LLCSell-1,099,6001,938,162$542,201
Q1 2021Longleaf PartnersBuy603,890603,890$168,939
Q1 2021Parnassus Endeavor FundSell-260,004314,412$87,957
Q1 2021Hillman Value FundBuy7,36027,289$7,634
Q1 2021Muhlenkamp & CoBuy3718,184$6,361
Q4 2020Renaissance Technologies LLCSell-779,1993,037,762$743,826
Q4 2020Hillman Value FundBuy29219,929$4,880
Q4 2020Muhlenkamp & CoBuy9418,147$4,443
Q3 2020Renaissance Technologies LLCSell-88,9613,816,961$1,082,795
Q3 2020Hillman Value FundBuy3,39119,637$5,571
Q3 2020Hancock Classic ValueSell-3862,857$810
Q3 2020Muhlenkamp & CoBuy22218,053$5,121
Q2 2020Renaissance Technologies LLCSell-567,9903,905,922$1,045,029
Q2 2020First Eagle U.S. ValueSell-199,72557,300$15,331
Q2 2020Hancock Classic ValueSell-43,9083,243$868
Q2 2020Hillman Value FundSell-13416,246$4,347
Q2 2020Muhlenkamp & CoBuy6317,831$4,771

Frequently asked questions about BIIB activity

  • Which institutional owners are buying BIIB?

    Institutional owners buying BIIB include investors who have either initiated new positions or increased their existing holdings based on recent SEC 13F filings. The activity table above highlights which funds added shares in the latest reporting periods and how their positions changed over time.

  • What does "buy" mean in BIIB activity?

    "Buy" means an investor increased their reported position in BIIB compared to the prior reporting period. This reflects growing exposure to BIOGEN INC (BIIB) rather than necessarily a brand-new position (though new positions also appear as buys when prior quantity was zero).

  • Is institutional interest in BIIB increasing?

    Institutional interest in BIIB can be assessed by comparing the number of tracked funds adding or increasing positions versus those trimming or exiting across the periods shown. A higher number of additions typically signals increasing participation among large filers, but it should be read alongside position sizes and the full table.

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