Tandem Diabetes CareTNDM
13F holders, Q1 2026 (March 31)274holders +5
40new positions
32sold out
7famous investors
$19.18avg. 13F price*
At the end of Q1 2026, 274 institutions reported holding Tandem Diabetes Care Inc. (TNDM) in their 13F filings, up 5 from Q4 2025. 40 opened new positions and 32 sold out. The largest holders were BlackRock, Inc. ($204.9M), Sessa Capital IM, L.P. ($90.7M) and Vanguard Portfolio Management LLC ($76.6M). 7 famous investors held it, including Ken Griffin (0.0% of Citadel Advisors's portfolio), Steve Cohen (0.0% of Point72 Asset Management's portfolio) and David E. Shaw (0.0% of D. E. Shaw & Co.'s portfolio).
- Company
- Tandem Diabetes Care Inc.
- CUSIP
- 875372203
- Latest filing quarter
- Q2 2026
History
Number of 13F holders
Total Exit/New Position Q4 2025 → Q1 2026
| Institutions | Total Value | |
|---|---|---|
| New Positions | 40 | $74.4M |
| Exits | 32 | $27.7M |
All 13F filers, Q4 2025 → Q1 2026: 12,267,607 shares bought and 7,670,432 shares sold, net +4,597,175 shares. Counts holders who added, trimmed, opened or closed a position; split-adjusted.
Ownership 274 holders
| BlackRock, Inc. | 0.00% | Reduce -4.1% | 10,690,844 | $204.9M |
| Sessa Capital IM, L.P. | 1.73% | Reduce -5.4% | 4,730,757 | $90.7M |
| Vanguard Portfolio Management LLC | 0.00% | — | 3,993,333 | $76.6M |
| ArrowMark Colorado Holdings LLC | 1.58% | Add +7.4% | 3,103,609 | $59.5M |
| Vanguard Capital Management LLC | 0.00% | — | 3,038,919 | $58.3M |
| GW&K Investment Management, LLC | 0.45% | Add +0.5% | 2,689,106 | $51.5M |
| State Street Corp. | 0.00% | Add +0.8% | 2,662,260 | $51.0M |
| Driehaus Capital Management LLC | 0.32% | Add +43.1% | 2,304,414 | $44.2M |
| Goldman Sachs Group Inc. | 0.01% | Add +31.8% | 2,218,922 | $42.5M |
| Citadel Advisors | 0.03% | Add +5.0% | 2,192,667 | $42.0M |
| UBS Group AG | 0.01% | Add +390.1% | 2,047,801 | $39.3M |
| Paradice Investment Management LLC | 7.35% | Reduce -1.7% | 2,042,425 | $39.2M |
| Two Sigma Investments, LP | 0.03% | Add +55.1% | 1,864,194 | $35.7M |
| Geode Capital Management, LLC | 0.00% | Add +1.9% | 1,679,863 | $32.2M |
| Jennison Associates LLC | 0.02% | Reduce -17.9% | 1,658,448 | $31.8M |
| Jacobs Levy Equity Management, Inc. | 0.12% | Reduce -7.8% | 1,523,946 | $29.2M |
| Marshall Wace, LLP | 0.03% | Add +64.8% | 1,442,472 | $27.7M |
| Morgan Stanley | 0.00% | Reduce -34.8% | 1,357,542 | $26.0M |
| Freestone Grove Partners LP | 0.18% | Reduce -7.8% | 1,330,742 | $25.5M |
| First Light Asset Management, LLC | 2.26% | Add +20.7% | 1,314,715 | $25.2M |
| Baillie Gifford & Co. | 0.02% | Reduce -4.9% | 1,089,393 | $20.9M |
| Wellington Management Group LLP | 0.00% | Add +960.7% | 1,042,764 | $20.0M |
| Voya Investment Management LLC | 0.02% | Add +151.7% | 804,137 | $15.4M |
| D. E. Shaw & Co. | 0.01% | Reduce -8.2% | 783,906 | $15.0M |
| Soleus Capital Management, L.P. | 0.61% | New | 783,000 | $15.0M |
| Defilade Capital Management, L.P. | 2.05% | New | 761,905 | $14.6M |
| Millennium Management | 0.01% | Add +30.5% | 761,672 | $14.6M |
| FMR LLC | 0.00% | Add +6.2% | 714,011 | $13.7M |
| Northern Trust Corp. | 0.00% | Add +2.2% | 706,609 | $13.5M |
| Royce & Associates LP | 0.13% | Add +7.1% | 696,590 | $13.4M |
| Quantinno Capital Management LP | 0.02% | Add +123.5% | 653,870 | $12.5M |
| Charles Schwab Investment Management Inc. | 0.00% | Reduce -0.6% | 642,598 | $12.3M |
| ExodusPoint Capital Management, LP | 0.12% | New | 632,899 | $12.1M |
| Holocene Advisors, LP | 0.02% | Add +2807.5% | 477,359 | $9.2M |
| Vanguard Fiduciary Trust Co. | 0.00% | — | 471,658 | $9.0M |
| Aberdeen Group plc | 0.01% | Reduce -20.7% | 434,027 | $8.3M |
| Barclays PLC | 0.00% | Reduce -54.1% | 421,236 | $8.1M |
| Point72 Asset Management | 0.01% | New | 420,478 | $8.1M |
| Frontier Capital Management Co. LLC | 0.08% | Reduce -3.6% | 397,209 | $7.6M |
| Bank of America Corp. | 0.00% | Reduce -46.9% | 373,224 | $7.2M |
| Nuveen, LLC | 0.00% | Reduce -35.4% | 363,802 | $7.0M |
| JPMorgan Chase & Co. | 0.00% | Add +2.4% | 349,792 | $6.9M |
| DAFNA Capital Management LLC | 1.57% | No change | 355,208 | $6.8M |
| First Trust Advisors LP | 0.00% | New | 342,707 | $6.6M |
| Bank of New York Mellon Corp | 0.00% | Reduce -3.9% | 336,291 | $6.4M |
| AQR Capital Management | 0.00% | Reduce -2.3% | 331,916 | $6.4M |
| Principal Financial Group Inc. | 0.00% | Add +2.2% | 331,541 | $6.4M |
| Invesco Ltd. | 0.00% | Add +5.9% | 294,052 | $5.6M |
| Acadian Asset Management LLC | 0.01% | Reduce -29.2% | 278,116 | $5.3M |
| Sector Gamma As | 1.21% | No change | 267,091 | $5.1M |
| Edmond DE Rothschild Holding S.A. | 0.07% | No change | 258,200 | $4.9M |
| Beaconlight Capital, LLC | 2.74% | New | 253,877 | $4.9M |
| Trexquant Investment LP | 0.03% | Add +142.7% | 249,298 | $4.8M |
| Envestnet Asset Management Inc. | 0.00% | Add +9.7% | 243,248 | $4.7M |
| Public Sector Pension Investment Board | 0.01% | Add +3.4% | 242,596 | $4.7M |
| BNP Paribas Financial Markets | 0.00% | Reduce -83.3% | 208,713 | $4.0M |
| Susquehanna Portfolio Strategies, LLC | 0.06% | Add +210.3% | 206,193 | $4.0M |
| Royal Bank of Canada | 0.00% | Reduce -1.2% | 206,033 | $3.9M |
| Arrowstreet Capital, Limited Partnership | 0.00% | Add +42.6% | 193,556 | $3.7M |
| Rhumbline Advisers | 0.00% | Add +1.1% | 186,316 | $3.6M |
| Assenagon Asset Management S.A. | 0.01% | Reduce -85.5% | 178,640 | $3.4M |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC | 0.00% | Add +2.2% | 168,493 | $3.2M |
| Lisanti Capital Growth, LLC | 0.80% | Reduce -37.1% | 165,325 | $3.2M |
| Panagora Asset Management Inc. | 0.01% | Add +11.9% | 163,695 | $3.1M |
| Mizuho Markets Americas LLC | 0.08% | Add +8.8% | 157,362 | $3.0M |
| Legal & General Group Plc | 0.00% | Reduce -9.6% | 155,288 | $3.0M |
| Toronto Dominion Bank | 0.01% | New | 150,078 | $2.9M |
| Russell Investments Group, Ltd. | 0.00% | Add +3.8% | 133,596 | $2.6M |
| Swiss National Bank | 0.00% | No change | 133,300 | $2.6M |
| Raymond James Financial Inc. | 0.00% | Add +4.3% | 125,345 | $2.4M |
| Banque Pictet & Cie SA | 0.03% | Add +27.5% | 123,935 | $2.4M |
| Federated Hermes, Inc. | 0.00% | Add +495176.0% | 123,819 | $2.4M |
| Ameriprise Financial Inc. | 0.00% | Reduce -5.9% | 121,150 | $2.3M |
| Canada Pension Plan Investment Board | 0.00% | Reduce -33.3% | 118,439 | $2.3M |
| Algert Global LLC | 0.03% | Add +8.1% | 117,799 | $2.3M |
| Intech Investment Management LLC | 0.02% | Add +307.1% | 111,421 | $2.1M |
| Verition Fund Management LLC | 0.02% | Add +911.8% | 107,119 | $2.1M |
| Sei Investments Co. | 0.00% | Reduce -10.6% | 95,306 | $1.8M |
| Zurcher Kantonalbank (Zurich Cantonalbank) | 0.00% | Add +27.5% | 94,340 | $1.8M |
| PDT Partners, LLC | 0.11% | Reduce -15.0% | 93,805 | $1.8M |
| Universal- Beteiligungs- und Servicegesellschaft mbH | 0.00% | Reduce -1.9% | 87,357 | $1.7M |
| California State Teachers Retirement System | 0.00% | Add +30.8% | 84,255 | $1.6M |
| Alliancebernstein L.P. | 0.00% | Reduce -68.8% | 73,149 | $1.6M |
| Susquehanna International Group, LLP | 0.00% | Reduce -38.0% | 80,749 | $1.5M |
| Nierenberg Investment Management Company, LLC | 0.76% | Add +78.5% | 79,510 | $1.5M |
| Tudor Investment Corporation | 0.01% | Reduce -26.9% | 78,999 | $1.5M |
| Y-Intercept (Hong Kong) Ltd | 0.03% | Reduce -7.3% | 77,879 | $1.5M |
| Cerity Partners LLC | 0.00% | Reduce -0.7% | 76,228 | $1.5M |
| Rice Hall James & Associates, LLC | 0.08% | Add +16.8% | 72,878 | $1.4M |
| Formula Growth Ltd. | 0.61% | Reduce -0.1% | 70,828 | $1.4M |
| Prudential Financial Inc. | 0.00% | Add +6.8% | 69,404 | $1.3M |
| T. Rowe Price Associates Inc. | 0.00% | Add +20.9% | 68,661 | $1.3M |
| Citigroup Inc. | 0.00% | Add +272.1% | 68,346 | $1.3M |
| New York State Teachers Retirement System | 0.00% | Reduce -3.2% | 66,096 | $1.3M |
| Jones Financial Companies LLLP | 0.00% | Add +3638.0% | 58,388 | $1.2M |
| Cinctive Capital Management LP | 0.08% | New | 63,812 | $1.2M |
| Natixis Advisors, LLC | 0.00% | Add +7.1% | 61,084 | $1.2M |
| XTX Topco Ltd | 0.02% | New | 60,821 | $1.2M |
| Deutsche Bank AG | 0.00% | Add +11.8% | 60,629 | $1.2M |
| VANGUARD ASSET MANAGEMENT, Ltd | 0.00% | — | 58,288 | $1.1M |
"% of holder's portfolio" is TNDM's weight in each manager's 13F, not the share of Tandem Diabetes Care Inc. the manager owns.