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Castleark Management’s Rhythm Pharmaceuticals RYTM Stock Holding History

Castleark Management’s Portfolio RYTM Stock Details RYTM Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q2 		– Sell
-52,279
Closed -$4.55M – 343
2026
Q1 		$4.55M Sell
52,279
-12,200
-19% -$1.19M 0.15% 155
2025
Q4 		$6.9M Buy
64,479
+21,940
+52% +$2.33M 0.2% 120
2025
Q3 		$4.3M Buy
+42,539
New +$3.95M 0.12% 155
2025
Q1 		– Sell
-18,390
Closed -$1.03M – 334
2024
Q4 		$1.03M Sell
18,390
-870
-5% -$48.1K 0.04% 213
2024
Q3 		$1.01M Buy
19,260
+250
+1% +$12K 0.04% 198
2024
Q2 		$781K Sell
19,010
-44,890
-70% -$1.79M 0.03% 210
2024
Q1 		$2.77M Buy
+63,900
New +$2.8M 0.12% 161

Other funds holding RYTM

RCM
RA Capital Management Boston, Massachusetts $11.5B AUM 168.77% 1-Year Est. Return
BlackRock
BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return
BBA
Baker Bros. Advisors New York $20B AUM 154.41% 1-Year Est. Return
Primecap Management
Primecap Management Pasadena, California $169B AUM 114.72% 1-Year Est. Return
Vanguard Portfolio Management
Vanguard Portfolio Management Malvern, Pennsylvania $2.22T AUM
Vanguard Capital Management
Vanguard Capital Management Malvern, Pennsylvania $4.68T AUM
JP Morgan Chase
JP Morgan Chase New York $1.81T AUM 41.13% 1-Year Est. Return
PA
Perceptive Advisors New York $6.66B AUM 360.84% 1-Year Est. Return
State Street
State Street Boston, Massachusetts $3.37T AUM 44.26% 1-Year Est. Return
T. Rowe Price Associates
T. Rowe Price Associates Baltimore, Maryland $999B AUM 46.22% 1-Year Est. Return

Castleark Management's RYTM Position: Q2 2026 in Review

Castleark Management sold out of Rhythm Pharmaceuticals (RYTM) in Q2 2026, closing a stake of 52,279 shares — an estimated $4.55M sold.

Castleark Management first reported a position in RYTM in Q1 2024 and held it in 7 quarters. The position peaked at $6.9M in Q4 2025. 304 funds tracked by Wall St. Rank hold RYTM as of Q2 2026.

  • Castleark Management reported no remaining Rhythm Pharmaceuticals position as of Q2 2026 after selling out during the quarter.
  • Castleark Management sold 52,279 Rhythm Pharmaceuticals shares in Q2 2026, an estimated $4.55M.
  • Castleark Management first reported a position in Rhythm Pharmaceuticals in Q1 2024 and held it in 7 quarters.
  • Castleark Management's Rhythm Pharmaceuticals position peaked at $6.9M in Q4 2025.
  • 304 funds tracked by Wall St. Rank held Rhythm Pharmaceuticals as of Q2 2026.

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