IRTC iRhythm Technologies, Inc.
iRhythm Technologies, Inc. (IRTC) Institutional Ownership
What the institutions did with IRTC last quarter, from their 13F filings. Counting managers rather than shares is the point: a single index fund adding to a position tells you far less than four hundred separate managers all deciding to. Positions as reported for the quarter ended June 30, 2026.
Every manager below opens. Subscribers can see any firm's whole portfolio — every position, its weight, and what they bought, trimmed and exited last quarter.
Sign in or subscribeLargest holders
| Manager | Shares | % of reported |
|---|---|---|
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM | 5.2M | 12.8% |
| BlackRock, Inc. | 3.0M | 7.3% |
| RTW INVESTMENTS, LP | 2.2M | 5.3% |
| VANGUARD PORTFOLIO MANAGEMENT LLC | 1.9M | 4.7% |
| Artisan Partners Limited Partnership | 1.7M | 4.1% |
| VANGUARD CAPITAL MANAGEMENT LLC | 1.5M | 3.6% |
| MILLENNIUM MANAGEMENT LLC | 1.4M | 3.4% |
| FMR LLC | 1.2M | 2.9% |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC | 944.5K | 2.3% |
| GEODE CAPITAL MANAGEMENT, LLC | 881.9K | 2.2% |
| EVENTIDE ASSET MANAGEMENT, LLC | 880.3K | 2.2% |
| BNP PARIBAS ASSET MANAGEMENT Holding S.A. | 866.5K | 2.1% |
| STATE STREET CORP | 856.5K | 2.1% |
| Holocene Advisors, LP | 783.6K | 1.9% |
| JPMORGAN CHASE & CO | 766.2K | 1.9% |
| Stephens Investment Management Group LLC | 693.4K | 1.7% |
| FULLER & THALER ASSET MANAGEMENT, INC. | 685.5K | 1.7% |
| BRAIDWELL LP | 654.3K | 1.6% |
| D. E. Shaw & Co., Inc. | 629.7K | 1.5% |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE | 561.3K | 1.4% |
| BLAIR WILLIAM & CO/IL | 524.7K | 1.3% |
| BANK OF AMERICA CORP /DE/ | 465.7K | 1.1% |
| Polar Capital Holdings Plc | 458.1K | 1.1% |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP | 450.9K | 1.1% |
| SCHRODER INVESTMENT MANAGEMENT GROUP | 448.3K | 1.1% |
Largest changes
| Manager | Action | Previous | Current | Change |
|---|---|---|---|---|
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM | Increased | 37.3K | 5.2M | +5.2M |
| RTW INVESTMENTS, LP | Increased | 1.7M | 2.2M | +514.1K |
| Holocene Advisors, LP | Reduced | 1.2M | 783.6K | -465.0K |
| MACKENZIE FINANCIAL CORP | Sold Out | 371.5K | 0 | -371.5K |
| Point72 Asset Management, L.P. | Reduced | 599.4K | 273.2K | -326.2K |
| WESTFIELD CAPITAL MANAGEMENT CO LP | New | 0 | 288.9K | +288.9K |
| Invesco Ltd. | Reduced | 297.5K | 22.1K | -275.3K |
| BlackRock, Inc. | Increased | 2.7M | 3.0M | +244.2K |
| Assenagon Asset Management S.A. | Reduced | 270.2K | 44.3K | -225.9K |
| Artisan Partners Limited Partnership | Increased | 1.5M | 1.7M | +209.4K |
| MILLENNIUM MANAGEMENT LLC | Reduced | 1.6M | 1.4M | -201.6K |
| SCHRODER INVESTMENT MANAGEMENT GROUP | Increased | 247.7K | 448.3K | +200.5K |
| Balyasny Asset Management L.P. | Reduced | 194.4K | 5.6K | -188.9K |
| Capital Research Global Investors | Reduced | 509.6K | 335.2K | -174.4K |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE | Increased | 390.6K | 561.3K | +170.7K |
| FMR LLC | Reduced | 1.4M | 1.2M | -169.9K |
| Allspring Global Investments Holdings, LLC | Reduced | 467.1K | 300.1K | -167.1K |
| JANE STREET GROUP, LLC | Increased | 112.9K | 275.3K | +162.4K |
| Prosight Management, LP | Increased | 10.0K | 165.5K | +155.5K |
| Ophir Asset Management Pty Ltd | Reduced | 335.8K | 201.5K | -134.3K |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP | Reduced | 582.9K | 450.9K | -132.0K |
| Stephens Investment Management Group LLC | Increased | 561.5K | 693.4K | +131.9K |
| EVENTIDE ASSET MANAGEMENT, LLC | Increased | 760.8K | 880.3K | +119.5K |
| PERCEPTIVE ADVISORS LLC | Increased | 105.0K | 223.8K | +118.7K |
| VANGUARD PORTFOLIO MANAGEMENT LLC | Increased | 1.8M | 1.9M | +117.6K |
13F filings are due 45 days after quarter end and cover long positions in U.S.-listed equities only, so this is a lagged and partial picture: shorts, bonds and foreign listings never appear. Options positions are excluded here rather than folded into the share counts. Political ownership is coming.