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
Q3 		$236M Buy
2,480,692
+272,097
+12% +$29M 0.77% 25
2026
Q2 		$245M Buy
2,208,595
+279,472
+14% +$25.3M 0.8% 21
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

BlackRock
BlackRock New York $6.79T AUM 37.06% 1-Year Est. Return
JP Morgan Chase
JP Morgan Chase New York $1.84T AUM 33.86% 1-Year Est. Return
Vanguard Portfolio Management
Vanguard Portfolio Management Malvern, Pennsylvania $2.21T AUM
Primecap Management
Primecap Management Pasadena, California $161B AUM 86.05% 1-Year Est. Return
Vanguard Capital Management
Vanguard Capital Management Malvern, Pennsylvania $4.76T AUM
State Street
State Street Boston, Massachusetts $3.44T AUM 36.12% 1-Year Est. Return
Federated Hermes
Federated Hermes Pittsburgh, Pennsylvania $71.4B AUM 33.43% 1-Year Est. Return
Capital Research Global Investors
Capital Research Global Investors Los Angeles, California $704B AUM 26.74% 1-Year Est. Return
Geode Capital Management
Geode Capital Management Boston, Massachusetts $1.92T AUM 36.1% 1-Year Est. Return
CC
Checkpoint Capital San Francisco, California $442M AUM 36.72% 1-Year Est. Return

Westfield Capital Management's RYTM Position: Q3 2026 in Review

Westfield Capital Management increased its Rhythm Pharmaceuticals (RYTM) stake by 12% in Q3 2026, buying an estimated $29M and bringing the position to 2,480,692 shares worth $236M. The position accounts for 0.77% of the portfolio, ranked #25.

Westfield Capital Management first reported a position in RYTM in Q1 2025 and has held it in 7 quarters since. The position peaked at $245M in Q2 2026. 239 funds tracked by Wall St. Rank hold RYTM as of Q3 2026.

  • Westfield Capital Management held 2,480,692 shares of Rhythm Pharmaceuticals worth $236M as of Q3 2026.
  • Westfield Capital Management bought 272,097 Rhythm Pharmaceuticals shares in Q3 2026, an estimated $29M.
  • Rhythm Pharmaceuticals made up 0.77% of Westfield Capital Management's portfolio in Q3 2026, its #25 holding.
  • Westfield Capital Management first reported a position in Rhythm Pharmaceuticals in Q1 2025 and has held it in 7 quarters since.
  • Westfield Capital Management's Rhythm Pharmaceuticals position peaked at $245M in Q2 2026.
  • 239 funds tracked by Wall St. Rank held Rhythm Pharmaceuticals as of Q3 2026.

Based on Westfield Capital Management's 13F filing for Q3 2026, filed 12 Nov 2026.