RSCM
AMLX icon

Rock Springs Capital Management’s Amylyx Pharmaceuticals AMLX Stock Holding History

Rock Springs Capital Management’s Portfolio AMLX Stock Details AMLX Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q2 		$8.98M Hold
499,764
– – 0.44% 59
2026
Q1 		$6.95M Hold
499,764
– – 0.41% 56
2025
Q4 		$6.04M Hold
499,764
– – 0.31% 65
2025
Q3 		$6.79M Hold
499,764
– – 0.4% 60
2025
Q2 		$3.2M Buy
499,764
+156,536
+46% +$761K 0.2% 70
2025
Q1 		$1.22M Buy
+343,228
New +$1.22M 0.07% 86
2024
Q2 		– Sell
-1,011,412
Closed -$2.87M – 114
2024
Q1 		$2.87M Buy
1,011,412
+476,400
+89% +$6.23M 0.07% 102
2023
Q4 		$7.88M Sell
535,012
-1,010,004
-65% -$15.5M 0.19% 75
2023
Q3 		$28.3M Buy
1,545,016
+400
+0% +$8.46K 0.76% 45
2023
Q2 		$33.3M Buy
1,544,616
+91,800
+6% +$2.48M 0.79% 42
2023
Q1 		$42.6M Buy
1,452,816
+223,179
+18% +$7.75M 1.02% 33
2022
Q4 		$45.4M Buy
1,229,637
+825,900
+205% +$29.3M 1.09% 33
2022
Q3 		$11.4M Sell
403,737
-570,370
-59% -$14.2M 0.29% 74
2022
Q2 		$18.8M Sell
974,107
-24,200
-2% -$287K 0.55% 54
2022
Q1 		$12.8M Buy
+998,307
New +$22.5M 0.32% 76

Other funds holding AMLX

Fidelity Investments
Fidelity Investments Boston, Massachusetts $2.3T AUM 54.33% 1-Year Est. Return
BlackRock
BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return
PA
Perceptive Advisors New York $6.66B AUM 360.84% 1-Year Est. Return
TCM
TCG Crossover Management Palo Alto, California $4.16B AUM 983.43% 1-Year Est. Return
CC
Commodore Capital New York $1.68B AUM 375.52% 1-Year Est. Return
JT
Jupiter Topco New York $245B AUM
SVCM
Saturn V Capital Management Austin, Texas $697M AUM 628.57% 1-Year Est. Return
Vanguard Capital Management
Vanguard Capital Management Malvern, Pennsylvania $4.68T AUM
Morgan Stanley
Morgan Stanley New York $1.89T AUM 35.08% 1-Year Est. Return
DCM
Driehaus Capital Management Chicago, Illinois $17.3B AUM 211.34% 1-Year Est. Return

Rock Springs Capital Management's AMLX Position: Q2 2026 in Review

Rock Springs Capital Management held its Amylyx Pharmaceuticals (AMLX) position steady in Q2 2026 at 499,764 shares worth $8.98M. The position accounts for 0.44% of the portfolio, ranked #59.

Rock Springs Capital Management first reported a position in AMLX in Q1 2022 and has held it in 15 quarters since. The position peaked at $45.4M in Q4 2022. 206 funds tracked by Wall St. Rank hold AMLX as of Q2 2026.

  • Rock Springs Capital Management held 499,764 shares of Amylyx Pharmaceuticals worth $8.98M as of Q2 2026.
  • Rock Springs Capital Management left its Amylyx Pharmaceuticals share count unchanged in Q2 2026.
  • Amylyx Pharmaceuticals made up 0.44% of Rock Springs Capital Management's portfolio in Q2 2026, its #59 holding.
  • Rock Springs Capital Management first reported a position in Amylyx Pharmaceuticals in Q1 2022 and has held it in 15 quarters since.
  • Rock Springs Capital Management's Amylyx Pharmaceuticals position peaked at $45.4M in Q4 2022.
  • 206 funds tracked by Wall St. Rank held Amylyx Pharmaceuticals as of Q2 2026.

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