Westfield Capital Management
RYTM icon

Westfield Capital Management’s Rhythm Pharmaceuticals RYTM Stock Holding History

Westfield Capital 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
Q1 		$168M Buy
1,929,123
+661,965
+52% +$64.4M 0.7% 26
2025
Q4 		$136M Buy
1,267,158
+198,154
+19% +$21M 0.57% 40
2025
Q3 		$108M Sell
1,069,004
-560,464
-34% -$52M 0.45% 56
2025
Q2 		$103M Buy
1,629,468
+288,376
+22% +$17.7M 0.43% 61
2025
Q1 		$71M Buy
+1,341,092
New +$74.4M 0.35% 87

Other funds holding RYTM

RCM
RA Capital Management Boston, Massachusetts $9.44B AUM 157.3% 1-Year Est. Return
BlackRock
BlackRock New York $5.72T AUM 30.48% 1-Year Est. Return
BBA
Baker Bros. Advisors New York $17.4B AUM 131.5% 1-Year Est. Return
Primecap Management
Primecap Management Pasadena, California $127B AUM 44.11% 1-Year Est. Return
VPM
Vanguard Portfolio Management Malvern, Pennsylvania $1.91T AUM
VCM
Vanguard Capital Management Malvern, Pennsylvania $4.04T AUM
PA
Perceptive Advisors New York $5.12B AUM 314.02% 1-Year Est. Return
State Street
State Street Boston, Massachusetts $2.9T AUM 29.55% 1-Year Est. Return
Goldman Sachs
Goldman Sachs New York $871B AUM 31.28% 1-Year Est. Return
Fidelity Investments
Fidelity Investments Boston, Massachusetts $1.9T AUM 41.92% 1-Year Est. Return

Westfield Capital Management's RYTM Position: Q1 2026 in Review

Westfield Capital Management increased its Rhythm Pharmaceuticals (RYTM) stake by 52% in Q1 2026, buying an estimated $64.4M and bringing the position to 1,929,123 shares worth $168M. The position accounts for 0.7% of the portfolio, ranked #26.

Westfield Capital Management first reported a position in RYTM in Q1 2025 and has held it in 5 quarters since. 285 funds tracked by Wall St. Rank hold RYTM as of Q1 2026.

  • Westfield Capital Management held 1,929,123 shares of Rhythm Pharmaceuticals worth $168M as of Q1 2026.
  • Westfield Capital Management bought 661,965 Rhythm Pharmaceuticals shares in Q1 2026, an estimated $64.4M.
  • Rhythm Pharmaceuticals made up 0.7% of Westfield Capital Management's portfolio in Q1 2026, its #26 holding.
  • Westfield Capital Management first reported a position in Rhythm Pharmaceuticals in Q1 2025 and has held it in 5 quarters since.
  • 285 funds tracked by Wall St. Rank held Rhythm Pharmaceuticals as of Q1 2026.

Based on Westfield Capital Management's 13F filing for Q1 2026, filed 11 May 2026.