iRhythm Holdings, Inc. IRTC
CIK 0001388658 · CUSIP 450056106
Quarter-end disclosures, not live holdings.
Top 20 institutions
Weight means this stock's share of the manager's own portfolio.
| # | Manager | Value | Manager weight | Change vs prior | Source | |
|---|---|---|---|---|---|---|
| 01 | BlackRock, Inc. CIK 2012383 · View history | $355.15M 2,985,667 shares | 0.01% | +244.16K(+8.9%)Added | SEC filing ↗ Aug 7, 2026 | ▾ |
| 02 | RTW INVESTMENTS, LP CIK 1493215 · View history | $259.62M 2,182,631 shares | 2.22% | +514.13K(+30.8%)Added | SEC filing ↗ Aug 14, 2026 | ▾ |
| 03 | VANGUARD PORTFOLIO MANAGEMENT LLC CIK 2100121 · View history | $227.67M 1,913,976 shares | 0.01% | +117.60K(+6.5%)Added | SEC filing ↗ Aug 13, 2026 | ▾ |
| 04 | Artisan Partners Limited Partnership CIK 1466153 · View history | $197.49M 1,660,307 shares | 0.32% | +209.40K(+14.4%)Added | SEC filing ↗ Aug 13, 2026 | ▾ |
| 05 | VANGUARD CAPITAL MANAGEMENT LLC CIK 2100119 · View history | $174.05M 1,463,211 shares | 0.00% | +17.50K(+1.2%)Added | SEC filing ↗ Aug 13, 2026 | ▾ |
| 06 | MILLENNIUM MANAGEMENT LLC CIK 1273087 · View history | $167.30M 1,406,454 shares | 0.11% | -201.56K(-12.5%)Reduced | SEC filing ↗ Aug 14, 2026 | ▾ |
| 07 | FMR LLC CIK 315066 · View history | $141.79M 1,191,982 shares | 0.01% | -169.94K(-12.5%)Reduced | SEC filing ↗ Aug 13, 2026 | ▾ |
| 08 | UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC CIK 861177 · View history | $112.35M 944,517 shares | 0.02% | -102.94K(-9.8%)Reduced | SEC filing ↗ Aug 13, 2026 | ▾ |
| 09 | GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history | $104.92M 881,899 shares | 0.01% | +64.79K(+7.9%)Added | SEC filing ↗ Aug 12, 2026 | ▾ |
| 10 | EVENTIDE ASSET MANAGEMENT, LLC CIK 1442891 · View history | $104.71M 880,338 shares | 1.40% | +119.51K(+15.7%)Added | SEC filing ↗ Aug 14, 2026 | ▾ |
| 11 | BNP PARIBAS ASSET MANAGEMENT Holding S.A. CIK 1520354 · View history | $103.07M 866,528 shares | 0.10% | +104.47K(+13.7%)Added | SEC filing ↗ Aug 13, 2026 | ▾ |
| 12 | STATE STREET CORP CIK 93751 · View history | $101.88M 856,517 shares | 0.00% | +68.22K(+8.7%)Added | SEC filing ↗ Aug 7, 2026 | ▾ |
| 13 | Holocene Advisors, LP CIK 1700574 · View history | $93.21M 783,636 shares | 0.21% | -465.02K(-37.2%)Reduced | SEC filing ↗ Aug 14, 2026 | ▾ |
| 14 | JPMORGAN CHASE & CO CIK 19617 · View history | $90.92M 766,216 shares | 0.01% | +51.32K(+7.2%)Added | SEC filing ↗ Aug 12, 2026 | ▾ |
| 15 | Stephens Investment Management Group LLC CIK 1314440 · View history | $82.48M 693,437 shares | 0.88% | +131.91K(+23.5%)Added | SEC filing ↗ Jul 29, 2026 | ▾ |
| 16 | FULLER & THALER ASSET MANAGEMENT, INC. CIK 1082327 · View history | $81.54M 685,496 shares | 0.22% | +10.80K(+1.6%)Added | SEC filing ↗ Aug 12, 2026 | ▾ |
| 17 | BRAIDWELL LP CIK 1920938 · View history | $77.82M 654,262 shares | 2.88% | +44.07K(+7.2%)Added | SEC filing ↗ Aug 14, 2026 | ▾ |
| 18 | D. E. Shaw & Co., Inc. CIK 1009207 · View history | $74.90M 629,686 shares | 0.05% | +75.42K(+13.6%)Added | SEC filing ↗ Aug 14, 2026 | ▾ |
| 19 | MANUFACTURERS LIFE INSURANCE COMPANY, THE CIK 928047 · Amended · View history | $66.76M 561,251 shares | 0.05% | +170.67K(+43.7%)Added | SEC filing ↗ Sep 9, 2026 | ▾ |
| 20 | BLAIR WILLIAM & CO/IL CIK 902367 · View history | $62.41M 524,690 shares | 0.16% | -103.69K(-16.5%)Reduced | SEC filing ↗ Aug 11, 2026 | ▾ |
Showing 20 / 304 institutions. The complete set is available through the API.
Coverage & totals by quarter
Reporting institutions by quarter
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