Dark Forest Capital Management’s Biogen BIIB Stock Holding History

Dark Forest Capital Management’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
2026 Q2	–	Sell	-15,736	Closed	-$2.88M	–	811
2026 Q1	$2.88M	Buy	+15,736	New	+$2.9M	0.26%	96
2024 Q4	–	Sell	-2,797	Closed	-$542K	–	950
2024 Q3	$542K	Buy	+2,797	New	+$585K	0.07%	351
2022 Q4	–	Sell	-42	Closed	-$11K	–	1157
2022 Q3	$11K	Buy	+42	New	+$8.92K	﹤0.01%	719
2022 Q2	–	Sell	-15	Closed	-$3K	–	910
2022 Q1	$3K	Sell	15 -8	-35%	-$1.74K	﹤0.01%	1144
2021 Q4	$6K	Buy	+23	New	+$5.91K	﹤0.01%	1083

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

Dark Forest Capital Management's BIIB Position: Q2 2026 in Review

Dark Forest Capital Management sold out of Biogen (BIIB) in Q2 2026, closing a stake of 15,736 shares — an estimated $2.88M sold.

Dark Forest Capital Management first reported a position in BIIB in Q4 2021 and held it in 5 quarters. The position peaked at $2.88M in Q1 2026. 1,043 funds tracked by Wall St. Rank hold BIIB as of Q2 2026.

Dark Forest Capital Management reported no remaining Biogen position as of Q2 2026 after selling out during the quarter.
Dark Forest Capital Management sold 15,736 Biogen shares in Q2 2026, an estimated $2.88M.
Dark Forest Capital Management first reported a position in Biogen in Q4 2021 and held it in 5 quarters.
Dark Forest Capital Management's Biogen position peaked at $2.88M in Q1 2026.
1,043 funds tracked by Wall St. Rank held Biogen as of Q2 2026.

Based on Dark Forest Capital Management's 13F filing for Q2 2026, filed 14 Aug 2026.