Atom Investors’s Biogen BIIB Stock Holding History

Atom Investors’s Portfolio BIIB Stock Details BIIB Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2021 Q3	–	Sell	-15,900	Closed	-$5.51M	–	316
2021 Q2	$5.51M	Buy	+15,900	New	+$4.82M	0.69%	25

Other funds holding BIIB

Fidelity Investments Boston, Massachusetts $2.3T AUM 54.33% 1-Year Est. Return

BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return

Primecap Management Pasadena, California $169B AUM 114.72% 1-Year Est. Return

Vanguard Capital Management Malvern, Pennsylvania $4.68T AUM

State Street Boston, Massachusetts $3.37T AUM 44.26% 1-Year Est. Return

Vanguard Portfolio Management Malvern, Pennsylvania $2.22T AUM

Geode Capital Management Boston, Massachusetts $1.88T AUM 44.46% 1-Year Est. Return

Wellington Management Group Boston, Massachusetts $580B AUM 38.23% 1-Year Est. Return

Norges Bank Oslo, Norway $1T AUM

Morgan Stanley New York $1.89T AUM 35.08% 1-Year Est. Return

Atom Investors's BIIB Position: Q2 2026 in Review

Atom Investors sold out of Biogen (BIIB) in Q2 2026, closing a stake of 24,749 shares — an estimated $4.54M sold.

Atom Investors first reported a position in BIIB in Q1 2019 and held it in 13 quarters. The position peaked at $11.1M in Q3 2019. 1,045 funds tracked by Wall St. Rank hold BIIB as of Q2 2026.

Atom Investors reported no remaining Biogen position as of Q2 2026 after selling out during the quarter.
Atom Investors sold 24,749 Biogen shares in Q2 2026, an estimated $4.54M.
Atom Investors first reported a position in Biogen in Q1 2019 and held it in 13 quarters.
Atom Investors's Biogen position peaked at $11.1M in Q3 2019.
1,045 funds tracked by Wall St. Rank held Biogen as of Q2 2026.

Based on Atom Investors's 13F filing for Q2 2026, filed 14 Aug 2026.