TNDM Tandem Diabetes Care, Inc.
Tandem Diabetes Care, Inc. (TNDM) Institutional Ownership
What the institutions did with TNDM 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 September 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 subscribeOwnership map
Each block is one manager, sized by shares held and colored by how much they moved the position last quarter. Green added, red cut, grey stood pat.
Largest holders
| Manager | Shares | % of reported |
|---|---|---|
| Paradice Investment Management LLC | 2.0M | 21.0% |
| GEODE CAPITAL MANAGEMENT, LLC | 1.6M | 16.6% |
| ROYCE & ASSOCIATES LP | 848.2K | 8.9% |
| BANK OF MONTREAL /CAN/ | 736.2K | 7.7% |
| BARCLAYS PLC | 425.2K | 4.4% |
| Jefferies Financial Group Inc. | 422.3K | 4.4% |
| Bank of New York Mellon Corp | 348.3K | 3.6% |
| PRINCIPAL FINANCIAL GROUP INC | 337.1K | 3.5% |
| ACADIAN ASSET MANAGEMENT LLC | 293.7K | 3.1% |
| Fideuram Asset Management (Ireland) dac | 244.8K | 2.6% |
| Squarepoint Ops LLC | 241.5K | 2.5% |
| Inspire Investing, LLC | 183.1K | 1.9% |
| HUSSMAN STRATEGIC ADVISORS, INC. | 168.0K | 1.8% |
| Y-Intercept (Hong Kong) Ltd | 147.9K | 1.5% |
| MACKENZIE FINANCIAL CORP | 146.6K | 1.5% |
| Russell Investments Group, Ltd. | 144.9K | 1.5% |
| MIZUHO MARKETS AMERICAS LLC | 137.8K | 1.4% |
| Aberdeen Group plc | 121.9K | 1.3% |
| BANQUE PICTET & CIE SA | 96.5K | 1.0% |
| INTECH INVESTMENT MANAGEMENT LLC | 88.1K | 0.9% |
| DEUTSCHE BANK AG\ | 69.1K | 0.7% |
| NEW YORK STATE TEACHERS RETIREMENT SYSTEM | 68.3K | 0.7% |
| Thrivent Financial for Lutherans | 44.3K | 0.5% |
| OPPENHEIMER ASSET MANAGEMENT INC. | 42.1K | 0.4% |
| LPL Financial LLC | 41.7K | 0.4% |
Largest changes
| Manager | Action | Previous | Current | Change |
|---|---|---|---|---|
| Aberdeen Group plc | Reduced | 441.7K | 121.9K | -319.8K |
| Alberta Investment Management Corp | Sold Out | 313.7K | 0 | -313.7K |
| Jefferies Financial Group Inc. | Increased | 166.5K | 422.3K | +255.8K |
| Fideuram Asset Management (Ireland) dac | New | 0 | 244.8K | +244.8K |
| GEODE CAPITAL MANAGEMENT, LLC | Reduced | 1.8M | 1.6M | -209.1K |
| BANK OF MONTREAL /CAN/ | Increased | 565.0K | 736.2K | +171.2K |
| HUSSMAN STRATEGIC ADVISORS, INC. | New | 0 | 168.0K | +168.0K |
| Y-Intercept (Hong Kong) Ltd | Reduced | 314.7K | 147.9K | -166.7K |
| ACADIAN ASSET MANAGEMENT LLC | Increased | 137.2K | 293.7K | +156.4K |
| MACKENZIE FINANCIAL CORP | New | 0 | 146.6K | +146.6K |
| Inspire Investing, LLC | Increased | 44.1K | 183.1K | +139.0K |
| Cambridge Investment Research Advisors, Inc. | Sold Out | 104.6K | 0 | -104.6K |
| BARCLAYS PLC | Increased | 350.4K | 425.2K | +74.8K |
| Assenagon Asset Management S.A. | Sold Out | 52.9K | 0 | -52.9K |
| ROYCE & ASSOCIATES LP | Reduced | 900.6K | 848.2K | -52.4K |
| FIDEURAM - INTESA SANPAOLO PRIVATE BANKING S.P.A. | Reduced | 84.9K | 33.4K | -51.5K |
| Squarepoint Ops LLC | Increased | 217.4K | 241.5K | +24.1K |
| GREENWOOD CAPITAL ASSOCIATES LLC | Sold Out | 23.1K | 0 | -23.1K |
| Paradice Investment Management LLC | Reduced | 2.0M | 2.0M | -16.6K |
| BANQUE PICTET & CIE SA | Reduced | 112.3K | 96.5K | -15.8K |
| Maryland State Retirement & Pension System | New | 0 | 15.3K | +15.3K |
| Savant Capital, LLC | New | 0 | 14.3K | +14.3K |
| Redhawk Wealth Advisors, Inc. | Sold Out | 13.7K | 0 | -13.7K |
| Olympiad Research LP | Sold Out | 13.5K | 0 | -13.5K |
| PNC Financial Services Group, Inc. | Reduced | 23.8K | 11.3K | -12.5K |
| State of Alaska, Department of Revenue | Reduced | 26.7K | 14.5K | -12.2K |
| SIMPLEX TRADING, LLC | New | 0 | 10.5K | +10.5K |
| Prosperitas Financial LLC | Sold Out | 10.0K | 0 | -10.0K |
| Provenance Wealth Advisors, LLC | New | 0 | 9.7K | +9.7K |
| Leonteq Securities AG | Reduced | 20.5K | 11.5K | -9.0K |
| VIRGINIA RETIREMENT SYSTEMS ET Al | Increased | 26.2K | 34.4K | +8.2K |
| WEALTH ENHANCEMENT ADVISORY SERVICES, LLC | Increased | 26.4K | 34.1K | +7.7K |
| INTECH INVESTMENT MANAGEMENT LLC | Increased | 81.1K | 88.1K | +7.0K |
| Wilmington Savings Fund Society, FSB | New | 0 | 6.5K | +6.5K |
| DEUTSCHE BANK AG\ | Reduced | 75.2K | 69.1K | -6.0K |
| VIRTUS ADVISERS, LLC | Sold Out | 4.5K | 0 | -4.5K |
| Fulcrum Asset Management LLP | Increased | 280 | 4.4K | +4.1K |
| Bank of New York Mellon Corp | Reduced | 352.2K | 348.3K | -3.9K |
| Russell Investments Group, Ltd. | Reduced | 148.6K | 144.9K | -3.7K |
| Bayforest Capital Ltd | Increased | 3.8K | 7.5K | +3.7K |
| State of Wyoming | Sold Out | 3.6K | 0 | -3.6K |
| INTERNATIONAL ASSETS INVESTMENT MANAGEMENT, LLC | Sold Out | 3.4K | 0 | -3.4K |
| Summit Global Investments | Increased | 21.7K | 24.8K | +3.0K |
| Farther Finance Advisors, LLC | Reduced | 2.9K | 589 | -2.3K |
| Police & Firemen's Retirement System of New Jersey | Reduced | 21.5K | 19.4K | -2.1K |
| Sterling Capital Management LLC | Increased | 245 | 2.3K | +2.1K |
| PRINCIPAL FINANCIAL GROUP INC | Increased | 335.1K | 337.1K | +2.0K |
| AdvisorNet Financial, Inc | Sold Out | 1.7K | 0 | -1.7K |
| Caitong International Asset Management Co., Ltd | Reduced | 20.0K | 18.5K | -1.5K |
| FIFTH THIRD BANCORP | Reduced | 22.1K | 21.1K | -1.1K |
| LPL Financial LLC | Reduced | 42.8K | 41.7K | -1.1K |
| OPPENHEIMER ASSET MANAGEMENT INC. | Increased | 41.0K | 42.1K | +1.1K |
| SALEM INVESTMENT COUNSELORS INC | Sold Out | 1.0K | 0 | -1.0K |
| SUMMIT SECURITIES GROUP LLC | New | 0 | 977 | +977 |
| Amundi | Increased | 11.7K | 12.6K | +958 |
| 180 WEALTH ADVISORS, LLC | Reduced | 24.9K | 24.1K | -874 |
| Versant Capital Management, Inc | Increased | 328 | 1.1K | +783 |
| Thrivent Financial for Lutherans | Reduced | 45.0K | 44.3K | -747 |
| Creative Planning | Increased | 16.2K | 16.9K | +722 |
| YOUSIF CAPITAL MANAGEMENT, LLC | Reduced | 18.5K | 18.0K | -550 |
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.