TANDEM DIABETES CARE INC TNDM
COM NEW · Common Stock · CUSIP 875372203 · ISIN US8753722037
U.S. healthcare company
- SectorHealth care
- IndustrySurgical & Medical Instruments & Apparatus
- HeadquartersSan Diego, CA
- Founded2008
- Websitetandemdiabetes.com
- FilingsSEC EDGAR
* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once ($4.2m this quarter). Holder counts are more reliable. Shares outstanding: 65.2m as of 2023-10-26, from the company's own SEC filing; the percentage can still exceed 100%: lent-out shares are counted by the lender and the buyer, and some reports overlap without saying so. Implied quarter-end price ≈ $29.58. Options: 12 managers hold calls ($13.2m notional), 16 hold puts ($18.3m).
Trends to Q4 2023
Institutional holders
Managers reporting a position, each quarter
Numbers
| Quarter | Holders |
|---|---|
| Q3 2022 | 298 |
| Q4 2022 | 295 |
| Q1 2023 | 275 |
| Q2 2023 | 248 |
| Q3 2023 | 226 |
| Q4 2023 | 268 |
Buyers vs sellers
Managers adding to or starting a position, vs cutting or selling out
Numbers
| Quarter | Bought or added | Cut or sold out |
|---|---|---|
| Q4 2022 | 150 | 149 |
| Q1 2023 | 150 | 144 |
| Q2 2023 | 125 | 151 |
| Q3 2023 | 104 | 135 |
| Q4 2023 | 150 | 117 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q1 2023 | $9.7m | $4.3m | 0.44 |
| Q2 2023 | $4.6m | $7.0m | 1.52 |
| Q3 2023 | $7.0m | $8.0m | 1.14 |
| Q4 2023 | $13.2m | $18.3m | 1.38 |
Biggest buyers
| ArrowMark Colorado Holdings LLC | Added | +1.3m |
| GW&K Investment Management, LLC | New | +1.2m |
| Point72 Asset Management, L.P. | Added | +989.0k |
| MORGAN STANLEY | Added | +969.7k |
| JACOBS LEVY EQUITY MANAGEMENT, INC | Added | +497.5k |
| NEXT CENTURY GROWTH INVESTORS LLC | New | +461.5k |
| BlackRock Inc. | Added | +389.2k |
| KINGDON CAPITAL MANAGEMENT, L.L.C. | New | +388.4k |
| Squarepoint Ops LLC | Added | +303.3k |
| MARSHALL WACE, LLP | Added | +172.9k |
Biggest sellers
| First Light Asset Management, LLC | Reduced | -1.1m |
| BROWN CAPITAL MANAGEMENT LLC | Reduced | -829.9k |
| Capital International Investors | Reduced | -710.6k |
| Paradice Investment Management LLC | Reduced | -438.2k |
| Chicago Capital, LLC | Reduced | -427.5k |
| EMINENCE CAPITAL, LP | Reduced | -319.6k |
| CITADEL ADVISORS LLC | Reduced | -284.7k |
| PEREGRINE CAPITAL MANAGEMENT LLC | Sold out | -243.4k |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Reduced | -232.6k |
| ALLIANCEBERNSTEIN L.P. | Reduced | -221.4k |
Biggest calls
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Reduced | $2.5m85.3k shares |
| PURA VIDA INVESTMENTS, LLC | New | $2.2m75.0k shares |
| SIMPLEX TRADING, LLC | Added | $2.1m69.4k shares |
| CITADEL ADVISORS LLC | Added | $1.6m53.2k shares |
| JANE STREET GROUP, LLC | Added | $1.3m43.4k shares |
| Cubist Systematic Strategies, LLC | Added | $1.3m42.5k shares |
| Walleye Capital LLC | Added | $905.1k30.6k shares |
| TWO SIGMA SECURITIES, LLC | New | $467.4k15.8k shares |
| WOLVERINE TRADING, LLC | New | $420.0k14.2k shares |
| Walleye Trading LLC | Added | $349.0k11.8k shares |
Biggest puts
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $4.5m152.1k shares |
| D. E. Shaw & Co., Inc. | Added | $4.0m136.5k shares |
| BOOTHBAY FUND MANAGEMENT, LLC | New | $2.1m70.4k shares |
| Caption Management, LLC | New | $1.8m59.2k shares |
| Walleye Trading LLC | Added | $1.2m40.8k shares |
| Cubist Systematic Strategies, LLC | Added | $999.8k33.8k shares |
| TWO SIGMA SECURITIES, LLC | Added | $854.9k28.9k shares |
| Walleye Capital LLC | Added | $662.6k22.4k shares |
| CITADEL ADVISORS LLC | Reduced | $585.7k19.8k shares |
| UBS Group AG | New | $417.1k14.1k shares |
Options at notional value: the value of the shares the contracts control, as filers report them, not what the options cost. Not included in the holders, shares or buying above.
Major shareholders (over 5%)
Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.
| Holder | Stake |
|---|---|
| BlackRock, Inc. 13G · institution filed 2025-04-29 | 15.2% |
| Sessa Capital (Master), L.P. 13G · passive investor new · filed 2025-05-15 | 6.7% |
| VANGUARD PORTFOLIO MANAGEMENT LLC 13G · institution new · filed 2026-04-29 | 5.9% |
| VANGUARD CAPITAL MANAGEMENT LLC 13G · institution new · filed 2026-04-30 | 5.2% |
Fell to 5% or below in the last year: Voya Financial, Inc. (0.2%, 2026-08-06), VANGUARD GROUP INC (0.0%, 2026-03-27; now reported by VANGUARD PORTFOLIO MANAGEMENT LLC), ArrowMark Colorado Holdings LLC (4.3%, 2026-02-17)
Insider purchases and sales in Q4 2023
Shares bought or sold by the company's own officers, directors and 10% owners, in the open market or privately, as they reported to the SEC on Form 4 (due within two business days of the trade). Grants, option exercises, shares withheld for tax and gifts aren't included.
Officers and directors buying vs selling
Number of people, by quarter (10% owners not included)
Numbers
| Quarter | Buying | Bought | Selling | Sold | Sold under a plan |
|---|---|---|---|---|---|
| Q1 2022 | 0 | — | 3 | $992.3k | — |
| Q2 2022 | 3 | $511.0k | 4 | $1.9m | — |
| Q3 2022 | 0 | — | 0 | — | — |
| Q4 2022 | 0 | — | 1 | $1.0m | — |
| Q1 2023 | 0 | — | 1 | $411.9k | — |
| Q2 2023 | 3 | $484.0k | 0 | — | — |
| Q3 2023 | 1 | $21.4k | 0 | — | — |
| Q4 2023 | 3 | $220.1k | 0 | — | — |
| Date | Insider | Trade | Value |
|---|---|---|---|
| 2023-11-27 | Allen Dick Director | Bought | $94.8k5.0k shares |
| 2023-11-08 | Vosseller Leigh EVP & CHIEF FINANCIAL OFFICER · Leigh A. Vosseller Trust | Bought | $95.4k6.2k shares |
| 2023-11-08 | Hansen Shannon Marie Chief Legal Officer · Shannon M. Hansen Trust | Bought | $29.9k1.9k shares |
Their holding: how much the trade added to or took from the insider's holding (direct, or the trust or fund named). The same trade is sometimes reported by more than one insider, such as a fund and the director who represents it; totals count it once. A value is left blank where the reported price is far from the market price (usually a typo).
Holders, Q4 2023
| Manager | Shares | Change |
|---|---|---|
| BlackRock Inc. 0.01% of their portfolio | 9.2m $273.5m | Added +389.2k |
| VANGUARD GROUP INC 0.00% of their portfolio | 7.0m $207.7m | Added +18.6k |
| Capital World Investors 0.03% of their portfolio | 6.4m $188.8m | Reduced -161.2k |
| EMINENCE CAPITAL, LP 2.99% of their portfolio | 5.2m $152.9m | Reduced -319.6k |
| FMR LLC 0.01% of their portfolio | 3.0m $88.1m | Reduced -14.8k |
| ArrowMark Colorado Holdings LLC 0.96% of their portfolio | 2.9m $86.8m | Added +1.3m |
| JANUS HENDERSON GROUP PLC 0.05% of their portfolio | 2.6m $76.2m | Reduced -93.5k |
| STATE STREET CORP 0.00% of their portfolio | 2.3m $67.3m | Added +104.7k |
| Bellevue Group AG 0.90% of their portfolio | 2.0m $58.9m | Reduced -150.5k |
| MORGAN STANLEY 0.00% of their portfolio | 1.7m $51.6m | Added +969.7k |
| Champlain Investment Partners, LLC 0.27% of their portfolio | 1.5m $45.3m | Reduced -86.0k |
| JACOBS LEVY EQUITY MANAGEMENT, INC 0.19% of their portfolio | 1.3m $38.2m | Added +497.5k |
| JENNISON ASSOCIATES LLC 0.03% of their portfolio | 1.3m $38.2m | Added +167.7k |
| GW&K Investment Management, LLC 0.34% of their portfolio | 1.2m $36.3m | New |
| Capital International Investors 0.01% of their portfolio | 1.1m $32.1m | Reduced -710.6k |
| Paradice Investment Management LLC 4.02% of their portfolio | 1.1m $32.0m | Reduced -438.2k |
| GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio | 1.0m $30.8m | Added +40.4k |
| TWO SIGMA ADVISERS, LP 0.07% of their portfolio | 1.0m $29.6m | Reduced -28.8k |
| Point72 Asset Management, L.P. 0.09% of their portfolio | 990.3k $29.3m | Added +989.0k |
| Stephens Investment Management Group LLC 0.42% of their portfolio | 962.3k $28.5m | Reduced -26.8k |
| VOLORIDGE INVESTMENT MANAGEMENT, LLC 0.11% of their portfolio | 952.6k $28.2m | Reduced -95.4k |
| BROWN CAPITAL MANAGEMENT LLC 0.33% of their portfolio | 734.6k $21.7m | Reduced -829.9k |
| TWO SIGMA INVESTMENTS, LP 0.05% of their portfolio | 701.4k $20.7m | Reduced -79.2k |
| MILLENNIUM MANAGEMENT LLC 0.02% of their portfolio | 630.8k $18.7m | Added +127.0k |
| Chicago Capital, LLC 0.51% of their portfolio | 476.9k $14.1m | Reduced -427.5k |
| NEXT CENTURY GROWTH INVESTORS LLC 1.33% of their portfolio | 461.5k $13.7m | New |
| Squarepoint Ops LLC 0.06% of their portfolio | 456.5k $13.5m | Added +303.3k |
| Bank of New York Mellon Corp 0.00% of their portfolio | 445.6k $13.2m | Reduced -69.1k |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.00% of their portfolio | 396.7k $11.7m | Added +29.7k |
| KINGDON CAPITAL MANAGEMENT, L.L.C. 1.10% of their portfolio | 388.4k $11.5m | New |
| Coronation Fund Managers Ltd. 0.31% of their portfolio | 376.4k $11.1m | Added +21.5k |
| CITADEL ADVISORS LLC 0.01% of their portfolio | 360.7k $10.7m | Reduced -284.7k |
| First Light Asset Management, LLC 0.86% of their portfolio | 360.2k $10.7m | Reduced -1.1m |
| MARSHALL WACE, LLP 0.02% of their portfolio | 351.9k $10.4m | Added +172.9k |
| NORTHERN TRUST CORP 0.00% of their portfolio | 350.8k $10.4m | Reduced -26.1k |
| PRINCIPAL FINANCIAL GROUP INC 0.01% of their portfolio | 344.3k $10.2m | Reduced -10.8k |
| NEW YORK STATE COMMON RETIREMENT FUND 0.01% of their portfolio | 315.5k $9.3m | Reduced -684 |
| AMERIPRISE FINANCIAL INC 0.00% of their portfolio | 313.6k $9.4m | Added +40.7k |
| FRED ALGER MANAGEMENT, LLC 0.05% of their portfolio | 302.8k $9.0m | Reduced -22.9k |
| BAILLIE GIFFORD & CO 0.01% of their portfolio | 262.6k $7.8m | Reduced -113 |
| Alberta Investment Management Corp 0.07% of their portfolio | 262.6k $7.8m | Added +21.0k |
| SILVERCREST ASSET MANAGEMENT GROUP LLC 0.05% of their portfolio | 255.3k $7.6m | Added +179 |
| Russell Investments Group, Ltd. 0.01% of their portfolio | 247.3k $7.3m | Added +109.5k |
| Invesco Ltd. 0.00% of their portfolio | 245.7k $7.3m | Reduced -28.1k |
| Invenomic Capital Management LP 0.38% of their portfolio | 241.0k $7.1m | Reduced -31.4k |
| KBC Group NV 0.03% of their portfolio | 239.9k $7.1m | Added +110.6k |
| TUDOR INVESTMENT CORP ET AL 0.09% of their portfolio | 231.7k $6.9m | Added +16.4k |
| GOLDMAN SACHS GROUP INC 0.00% of their portfolio | 225.7k $6.7m | Added +144.9k |
| DAFNA Capital Management LLC 1.56% of their portfolio | 220.7k $6.5m | Unchanged |
| BANQUE PICTET & CIE SA 0.07% of their portfolio | 198.3k $5.9m | Added +87.8k |
| JANE STREET GROUP, LLC 0.01% of their portfolio | 190.7k $5.6m | Added +144.0k |
| ENVESTNET ASSET MANAGEMENT INC 0.00% of their portfolio | 185.1k $5.5m | Added +166.9k |
| Connor, Clark & Lunn Investment Management Ltd. 0.03% of their portfolio | 184.3k $5.5m | Added +59.0k |
| Legal & General Group Plc 0.00% of their portfolio | 181.4k $5.4m | Reduced -1.4k |
| JPMORGAN CHASE & CO 0.00% of their portfolio | 172.8k $5.1m | Added +13.4k |
| RHUMBLINE ADVISERS 0.01% of their portfolio | 172.1k $5.1m | Reduced -1.2k |
| Trexquant Investment LP 0.11% of their portfolio | 162.0k $4.8m | Added +99.6k |
| FRONTIER CAPITAL MANAGEMENT CO LLC 0.04% of their portfolio | 145.9k $4.3m | Added +69 |
| Nuveen Asset Management, LLC 0.00% of their portfolio | 145.1k $4.3m | Reduced -11.0k |
| ALLIANCEBERNSTEIN L.P. 0.00% of their portfolio | 143.7k $4.3m | Reduced -221.4k |
| Weiss Multi-Strategy Advisers LLC 0.11% of their portfolio | 142.0k $4.2m | Added +111.3k |
| Public Sector Pension Investment Board 0.03% of their portfolio | 135.1k $4.0m | Added +54.6k |
| Mirae Asset Global Investments Co., Ltd. 0.01% of their portfolio | 130.9k $3.9m | Reduced -23.5k |
| Swiss National Bank 0.00% of their portfolio | 128.2k $3.8m | Reduced -13.8k |
| Skandinaviska Enskilda Banken AB (publ) 0.02% of their portfolio | 118.2k $3.5m | Unchanged |
| STATE OF WISCONSIN INVESTMENT BOARD 0.01% of their portfolio | 116.0k $3.4m | Added +31.4k |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP 0.01% of their portfolio | 113.8k $3.4m | Reduced -232.6k |
| PRUDENTIAL FINANCIAL INC 0.00% of their portfolio | 109.0k $3.2m | Reduced -20.8k |
| Balyasny Asset Management L.P. 0.01% of their portfolio | 106.4k $3.1m | New |
| Lisanti Capital Growth, LLC 0.74% of their portfolio | 105.9k $3.1m | New |
| RICE HALL JAMES & ASSOCIATES, LLC 0.18% of their portfolio | 104.4k $3.1m | Reduced -2.9k |
| D. E. Shaw & Co., Inc. 0.00% of their portfolio | 93.1k $2.8m | Reduced -157.8k |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.00% of their portfolio | 92.5k $2.7m | Reduced -2.7k |
| RAYMOND JAMES & ASSOCIATES 0.00% of their portfolio | 92.0k $2.7m | Added +51.7k |
| California Public Employees Retirement System 0.00% of their portfolio | 91.2k $2.7m | Unchanged |
| CREDIT SUISSE AG/ 0.00% of their portfolio | 89.1k $2.6m | Added +3.5k |
| TRUIST FINANCIAL CORP 0.00% of their portfolio | 87.5k $2.6m | New |
| BANK OF AMERICA CORP /DE/ 0.00% of their portfolio | 82.9k $2.5m | Reduced -7.3k |
| CANADA LIFE ASSURANCE Co 0.01% of their portfolio | 80.9k $2.4m | Added +1.5k |
| Gotham Asset Management, LLC 0.04% of their portfolio | 75.3k $2.2m | Added +60.6k |
| NEW YORK STATE TEACHERS RETIREMENT SYSTEM 0.00% of their portfolio | 70.0k $2.1m | Unchanged |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 0.00% of their portfolio | 68.7k $2.0m | Reduced -2.8k |
| ROYAL BANK OF CANADA 0.00% of their portfolio | 68.4k $2.0m | Added +37.7k |
| Bridgewater Associates, LP 0.01% of their portfolio | 68.4k $2.0m | Reduced -9.2k |
| HRT FINANCIAL LP 0.01% of their portfolio | 67.3k $2.0m | New |
| BEACONLIGHT CAPITAL, LLC 0.93% of their portfolio | 66.3k $2.0m | New |
| STATE BOARD OF ADMINISTRATION OF FLORIDA RETIREMENT SYSTEM 0.00% of their portfolio | 65.5k $1.9m | Added +48 |
| NOMURA HOLDINGS INC 0.02% of their portfolio | 59.7k $1.8m | Added +22.5k |
| Thrivent Financial for Lutherans 0.00% of their portfolio | 58.0k $1.7m | Reduced -1.5k |
| CAPITAL INTERNATIONAL SARL 0.06% of their portfolio | 56.2k $1.7m | Added +3.1k |
| TEXAS PERMANENT SCHOOL FUND CORP 0.01% of their portfolio | 56.0k $1.7m | Added +961 |
| CAPITAL INTERNATIONAL LTD /CA/ 0.08% of their portfolio | 55.9k $1.7m | Reduced -1.1k |
| Schonfeld Strategic Advisors LLC 0.01% of their portfolio | 54.7k $1.6m | New |
| DIMENSIONAL FUND ADVISORS LP 0.00% of their portfolio | 53.8k $1.6m | Reduced -81.2k |
| BARCLAYS PLC 0.00% of their portfolio | 49.6k $1.5m | Reduced -34.5k |
| M&T Bank Corp 0.01% of their portfolio | 49.6k $1.5m | Added +26.9k |
| DEUTSCHE BANK AG\ 0.00% of their portfolio | 46.8k $1.4m | Added +42.3k |
| CITIGROUP INC 0.00% of their portfolio | 43.0k $1.3m | Added +13.2k |
| FORMULA GROWTH LTD 0.39% of their portfolio | 40.7k $1.2m | Unchanged |
| State of Alaska, Department of Revenue 0.01% of their portfolio | 40.0k $1.2m | Reduced -511 |