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 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

BlackRock New York $5.72T AUM 30.48% 1-Year Est. Return

Primecap Management Pasadena, California $127B AUM 44.11% 1-Year Est. Return

Fidelity Investments Boston, Massachusetts $1.9T AUM 41.92% 1-Year Est. Return

VCM

Vanguard Capital Management Malvern, Pennsylvania $4.04T AUM

State Street Boston, Massachusetts $2.9T AUM 29.55% 1-Year Est. Return

VPM

Vanguard Portfolio Management Malvern, Pennsylvania $1.91T AUM

Geode Capital Management Boston, Massachusetts $1.61T AUM 30.72% 1-Year Est. Return

Wellington Management Group Boston, Massachusetts $535B AUM 26.23% 1-Year Est. Return

Morgan Stanley New York $1.66T AUM 25.57% 1-Year Est. Return

JP Morgan Chase New York $1.56T AUM 27.86% 1-Year Est. Return

Dark Forest Capital Management's BIIB Position: Q1 2026 in Review

Dark Forest Capital Management opened a new position in Biogen (BIIB) in Q1 2026: 15,736 shares worth $2.88M. The stake represents 0.26% of the portfolio and ranks #96 among its holdings. This is a return to the name: Dark Forest Capital Management previously reported a position in BIIB as recently as Q3 2024.

Dark Forest Capital Management first reported a position in BIIB in Q4 2021 and has held it in 5 quarters since. 1,002 funds tracked by Wall St. Rank hold BIIB as of Q1 2026.

Dark Forest Capital Management held 15,736 shares of Biogen worth $2.88M as of Q1 2026.
Biogen was a new Dark Forest Capital Management position in Q1 2026.
Biogen made up 0.26% of Dark Forest Capital Management's portfolio in Q1 2026, its #96 holding.
Dark Forest Capital Management first reported a position in Biogen in Q4 2021 and has held it in 5 quarters since.
1,002 funds tracked by Wall St. Rank held Biogen as of Q1 2026.

Based on Dark Forest Capital Management's 13F filing for Q1 2026, filed 15 May 2026.