Vault-13

TANDEM DIABETES CARE INC TNDM

COM NEW · Common Stock · CUSIP 875372203 · ISIN US8753722037

U.S. healthcare company

298 institutional holders
63,350,98663.4m shares reported held*
98.5% of all shares outstanding*
$3.0bnreported value*

* 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 ($7.1m this quarter). Holder counts are more reliable. Shares outstanding: 64.3m as of 2022-10-28, 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 ≈ $47.87. Options: 14 managers hold calls ($24.0m notional), 17 hold puts ($20.7m).

Biggest calls

CITADEL ADVISORS LLC — $5.6m117.2k shares
PURA VIDA INVESTMENTS, LLC — $4.8m100.0k shares
SUSQUEHANNA INTERNATIONAL GROUP, LLP — $4.6m95.1k shares
Walleye Trading LLC — $2.4m50.6k shares
JANE STREET GROUP, LLC — $1.8m38.4k shares
SIMPLEX TRADING, LLC — $1.2m25.1k shares
WOLVERINE TRADING, LLC — $1.1m22.6k shares
GROUP ONE TRADING LLC — $804.0k16.8k shares
D. E. Shaw & Co., Inc. — $799.0k16.7k shares
TWO SIGMA SECURITIES, LLC — $526.0k11.0k shares

Biggest puts

CITADEL ADVISORS LLC — $6.0m125.5k shares
SUSQUEHANNA INTERNATIONAL GROUP, LLP — $4.9m101.8k shares
PEAK6 Investments LLC — $3.6m74.4k shares
Cubist Systematic Strategies, LLC — $1.5m32.3k shares
JANE STREET GROUP, LLC — $1.1m22.0k shares
WOLVERINE TRADING, LLC — $925.0k18.6k shares
GROUP ONE TRADING LLC — $790.0k16.5k shares
TWO SIGMA SECURITIES, LLC — $617.0k12.9k shares
Parallax Volatility Advisers, L.P. — $479.0k10.0k shares
SIMPLEX TRADING, LLC — $449.0k9.4k 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.

HolderStakeChangeShares Last filed
BlackRock, Inc. 13G · institution filed 2025-04-29 15.2% 10.1m≈ $152.5m 2025-04-29
Sessa Capital (Master), L.P. 13G · passive investor new · filed 2025-05-15 6.7% new 4.5m≈ $67.4m 2025-05-15
VANGUARD PORTFOLIO MANAGEMENT LLC 13G · institution new · filed 2026-04-29 5.9% new 4.1m≈ $61.1m 2026-04-29
VANGUARD CAPITAL MANAGEMENT LLC 13G · institution new · filed 2026-04-30 5.2% new 3.6m≈ $53.6m 2026-04-30

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 Q3 2022

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)

BuyingSelling
10010Q4 20: 0 buyingQ4 20: 0 sellingQ1 21: 0 buyingQ1 21: 0 sellingQ1 21Q2 21: 0 buyingQ2 21: 0 sellingQ3 21: 0 buyingQ3 21: 0 sellingQ3 21Q4 21: 0 buyingQ4 21: 6 sellingQ1 22: 0 buyingQ1 22: 3 sellingQ1 22Q2 22: 3 buyingQ2 22: 4 sellingQ3 22: 0 buyingQ3 22: 0 sellingQ3 22
Numbers
QuarterBuyingBoughtSellingSoldSold under a plan
Q4 20200—0——
Q1 20210—0——
Q2 20210—0——
Q3 20210—0——
Q4 20210—6$18.8m—
Q1 20220—3$992.3k—
Q2 20223$511.0k4$1.9m—
Q3 20220—0——

None reported in Q3 2022.

Holders, Q3 2022

#ManagerLocationShares Value% of their portfolioChangeShares change
1 FMR LLC 0.04% of their portfolio BOSTON, MA 8,973,1919.0m $429.4m $429.4m 0.04% —
2 VANGUARD GROUP INC 0.01% of their portfolio Valley Forge, PA 6,194,2766.2m $296.4m $296.4m 0.01% —
3 BlackRock Inc. 0.01% of their portfolio New York, NY 6,093,2196.1m $291.6m $291.6m 0.01% —
4 Capital World Investors 0.05% of their portfolio LOS ANGELES, CA 4,555,6034.6m $218.0m $218.0m 0.05% —
5 Champlain Investment Partners, LLC 1.02% of their portfolio BURLINGTON, VT 3,123,9733.1m $149.5m $149.5m 1.02% —
6 BROWN CAPITAL MANAGEMENT LLC 1.35% of their portfolio BALTIMORE, MD 2,010,2302.0m $96.2m $96.2m 1.35% —
7 STATE STREET CORP 0.01% of their portfolio BOSTON, MA 1,783,0001.8m $85.3m $85.3m 0.01% —
8 EMINENCE CAPITAL, LP 1.63% of their portfolio NEW YORK, NY 1,590,7871.6m $76.1m $76.1m 1.63% —
9 Bellevue Group AG 1.08% of their portfolio ZURICH, V8 1,566,0151.6m $74.9m $74.9m 1.08% —
10 Invesco Ltd. 0.02% of their portfolio ATLANTA, GA 1,231,9861.2m $59.0m $59.0m 0.02% —
11 Stephens Investment Management Group LLC 0.89% of their portfolio LITTLE ROCK, AR 979,596979.6k $46.9m $46.9m 0.89% —
12 AXA S.A. 0.09% of their portfolio PARIS, I0 973,820973.8k $46.6m $46.6m 0.09% —
13 JANUS HENDERSON GROUP PLC 0.02% of their portfolio LONDON, X0 917,434917.4k $43.9m $43.9m 0.02% —
14 GEODE CAPITAL MANAGEMENT, LLC 0.01% of their portfolio BOSTON, MA 865,993866.0k $41.4m $41.4m 0.01% —
15 TWO SIGMA ADVISERS, LP 0.10% of their portfolio NEW YORK, NY 700,883700.9k $33.5m $33.5m 0.10% —
16 TWO SIGMA INVESTMENTS, LP 0.11% of their portfolio NEW YORK, NY 664,782664.8k $31.8m $31.8m 0.11% —
17 FEDERATED HERMES, INC. 0.09% of their portfolio PITTSBURGH, PA 663,340663.3k $31.7m $31.7m 0.09% —
18 Bank of New York Mellon Corp 0.01% of their portfolio NEW YORK, NY 653,808653.8k $31.3m $31.3m 0.01% —
19 NORGES BANK 0.01% of their portfolio OSLO, Q8 608,294608.3k $29.1m $29.1m 0.01% —
20 NORTHERN TRUST CORP 0.01% of their portfolio CHICAGO, IL 604,037604.0k $28.9m $28.9m 0.01% —
21 EATON VANCE MANAGEMENT 0.04% of their portfolio BOSTON, MA 561,500561.5k $26.9m $26.9m 0.04% —
22 TimesSquare Capital Management, LLC 0.36% of their portfolio NEW YORK, NY 546,465546.5k $26.1m $26.1m 0.36% —
23 EAGLE ASSET MANAGEMENT INC 0.16% of their portfolio ST PETERSBURG, FL 520,778520.8k $24.9m $24.9m 0.16% —
24 First Light Asset Management, LLC 2.35% of their portfolio Edina, MN 485,620485.6k $23.2m $23.2m 2.35% —
25 Chicago Capital, LLC 1.33% of their portfolio Chicago, IL 479,873479.9k $23.0m $23.0m 1.33% —
26 Nuveen Asset Management, LLC 0.01% of their portfolio CHICAGO, IL 477,654477.7k $22.9m $22.9m 0.01% —
27 Octagon Capital Advisors LP 3.92% of their portfolio NEW YORK, NY 474,929474.9k $22.7m $22.7m 3.92% —
28 MACQUARIE GROUP LTD 0.03% of their portfolio Sydney, NSW 2000, C3 445,226445.2k $21.3m $21.3m 0.03% —
29 WESTFIELD CAPITAL MANAGEMENT CO LP 0.16% of their portfolio BOSTON, MA 421,743421.7k $20.2m $20.2m 0.16% —
30 Soleus Capital Management, L.P. 2.70% of their portfolio GREENWICH, CT 415,200415.2k $19.9m $19.9m 2.70% —
31 PRICE T ROWE ASSOCIATES INC /MD/ 0.00% of their portfolio BALTIMORE, MD 403,945403.9k $19.3m $19.3m 0.00% —
32 Squarepoint Ops LLC 0.16% of their portfolio NEW YORK, NY 367,690367.7k $17.6m $17.6m 0.16% —
33 Granite Investment Partners, LLC 0.72% of their portfolio EL SEGUNDO, CA 346,224346.2k $16.6m $16.6m 0.72% —
34 NEW YORK STATE COMMON RETIREMENT FUND 0.02% of their portfolio ALBANY, NY 339,065339.1k $16.2m $16.2m 0.02% —
35 CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.01% of their portfolio SAN FRANCISCO, CA 333,964334.0k $16.0m $16.0m 0.01% —
36 WELLINGTON MANAGEMENT GROUP LLP 0.00% of their portfolio Boston, MA 328,866328.9k $15.7m $15.7m 0.00% —
37 MORGAN STANLEY 0.00% of their portfolio NEW YORK, NY 324,593324.6k $15.5m $15.5m 0.00% —
38 RTW INVESTMENTS, LP 0.36% of their portfolio NEW YORK, NY 322,000322.0k $15.4m $15.4m 0.36% —
39 CITADEL ADVISORS LLC 0.02% of their portfolio MIAMI, FL 309,806309.8k $14.8m $14.8m 0.02% —
40 EMERALD ADVISERS, LLC 0.74% of their portfolio LEOLA, PA 298,210298.2k $14.3m $14.3m 0.74% —
41 Balyasny Asset Management L.P. 0.05% of their portfolio Chicago, IL 293,520293.5k $14.0m $14.0m 0.05% —
42 GOLDMAN SACHS GROUP INC 0.00% of their portfolio NEW YORK, NY 290,622290.6k $13.9m $13.9m 0.00% —
43 Assenagon Asset Management S.A. 0.06% of their portfolio SENNINGERBERG, N4 290,215290.2k $13.9m $13.9m 0.06% —
44 BAILLIE GIFFORD & CO 0.01% of their portfolio EDINBURGH, X0 263,084263.1k $12.6m $12.6m 0.01% —
45 PRINCIPAL FINANCIAL GROUP INC 0.01% of their portfolio DES MOINES, IA 250,661250.7k $12.0m $12.0m 0.01% —
46 INTRINSIC EDGE CAPITAL MANAGEMENT LLC 1.32% of their portfolio CHICAGO, IL 247,391247.4k $11.8m $11.8m 1.32% —
47 WASATCH ADVISORS LP 0.08% of their portfolio SALT LAKE CITY, UT 241,295241.3k $11.5m $11.5m 0.08% —
48 EMERALD MUTUAL FUND ADVISERS TRUST 0.73% of their portfolio LEOLA, PA 240,460240.5k $11.5m $11.5m 0.73% —
49 AMERIPRISE FINANCIAL INC 0.00% of their portfolio MINNEAPOLIS, MN 218,594218.6k $10.5m $10.5m 0.00% —
50 ESSEX INVESTMENT MANAGEMENT CO LLC 1.67% of their portfolio BOSTON, MA 218,049218.0k $10.4m $10.4m 1.67% —
51 GILDER GAGNON HOWE & CO LLC 0.18% of their portfolio New York, NY 215,980216.0k $10.3m $10.3m 0.18% —
52 CAPITAL FUND MANAGEMENT S.A. 0.25% of their portfolio PARIS, I0 211,169211.2k $10.1m $10.1m 0.25% —
53 Eagle Health Investments LP 2.16% of their portfolio Greenwich, CT 196,400196.4k $9.4m $9.4m 2.16% —
54 PEREGRINE CAPITAL MANAGEMENT LLC 0.30% of their portfolio MINNEAPOLIS, MN 190,491190.5k $9.1m $9.1m 0.30% —
55 NOMURA HOLDINGS INC 0.09% of their portfolio TOKYO, M0 190,200190.2k $9.1m $9.1m 0.09% —
56 Cubist Systematic Strategies, LLC 0.07% of their portfolio STAMFORD, CT 185,078185.1k $8.9m $8.9m 0.07% —
57 RHUMBLINE ADVISERS 0.01% of their portfolio BOSTON, MA 181,239181.2k $8.7m $8.7m 0.01% —
58 FRED ALGER MANAGEMENT, LLC 0.04% of their portfolio NEW YORK, NY 179,673179.7k $8.6m $8.6m 0.04% —
59 KENNEDY CAPITAL MANAGEMENT LLC 0.23% of their portfolio ST LOUIS, MO 161,649161.6k $7.7m $7.7m 0.23% —
60 JPMORGAN CHASE & CO 0.00% of their portfolio NEW YORK, NY 161,003161.0k $7.7m $7.7m 0.00% —
61 WCM INVESTMENT MANAGEMENT, LLC 0.03% of their portfolio LAGUNA BEACH, CA 152,851152.9k $7.6m $7.6m 0.03% —
62 Lombard Odier Asset Management (Switzerland) SA 0.62% of their portfolio PETIT-LANCY, V8 152,631152.6k $7.3m $7.3m 0.62% —
63 Swiss National Bank 0.01% of their portfolio ZURICH, V8 151,700151.7k $7.3m $7.3m 0.01% —
64 California Public Employees Retirement System 0.01% of their portfolio Sacramento, CA 145,823145.8k $7.0m $7.0m 0.01% —
65 SILVERCREST ASSET MANAGEMENT GROUP LLC 0.06% of their portfolio NEW YORK, NY 142,837142.8k $6.8m $6.8m 0.06% —
66 Amundi 0.00% of their portfolio Paris, I0 133,575133.6k $7.0m $7.0m 0.00% —
67 PICTET ASSET MANAGEMENT SA 0.01% of their portfolio GENEVA 73, V8 128,590128.6k $6.2m $6.2m 0.01% —
68 BANK OF AMERICA CORP /DE/ 0.00% of their portfolio CHARLOTTE, NC 128,498128.5k $6.1m $6.1m 0.00% —
69 Skandinaviska Enskilda Banken AB (publ) 0.05% of their portfolio STOCKHOLM, V7 122,657122.7k $5.9m $5.9m 0.05% —
70 VOYA INVESTMENT MANAGEMENT LLC 0.01% of their portfolio ATLANTA, GA 122,352122.4k $5.9m $5.9m 0.01% —
71 Polar Asset Management Partners Inc. 0.07% of their portfolio TORONTO, A6 117,200117.2k $5.6m $5.6m 0.07% —
72 FRONTIER CAPITAL MANAGEMENT CO LLC 0.06% of their portfolio Boston, MA 114,501114.5k $5.5m $5.5m 0.06% —
73 SEI INVESTMENTS CO 0.01% of their portfolio OAKS, PA 109,620109.6k $5.2m $5.2m 0.01% —
74 Mirae Asset Global Investments Co., Ltd. 0.01% of their portfolio SEOUL, M5 105,845105.8k $5.1m $5.1m 0.01% —
75 Bridgewater Associates, LP 0.02% of their portfolio Westport, CT 101,743101.7k $4.9m $4.9m 0.02% —
76 AMERICAN INTERNATIONAL GROUP, INC. 0.04% of their portfolio New York, NY 101,649101.6k $4.9m $4.9m 0.04% —
77 OSTERWEIS CAPITAL MANAGEMENT INC 0.35% of their portfolio SAN FRANCISCO, CA 97,79097.8k $4.7m $4.7m 0.35% —
78 Legal & General Group Plc 0.00% of their portfolio London, X0 97,03897.0k $4.6m $4.6m 0.00% —
79 STATE OF WISCONSIN INVESTMENT BOARD 0.01% of their portfolio MADISON, WI 93,35593.4k $4.5m $4.5m 0.01% —
80 ALLIANCEBERNSTEIN L.P. 0.00% of their portfolio NASHVILLE, TN 92,47992.5k $4.4m $4.4m 0.00% —
81 Retirement Systems of Alabama 0.02% of their portfolio MONTGOMERY, AL 84,07784.1k $4.0m $4.0m 0.02% —
82 Point72 Asset Management, L.P. 0.02% of their portfolio STAMFORD, CT 82,73882.7k $4.0m $4.0m 0.02% —
83 UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.00% of their portfolio NEW YORK, NY 82,45882.5k $3.9m $3.9m 0.00% —
84 VOLORIDGE INVESTMENT MANAGEMENT, LLC 0.02% of their portfolio JUPITER, FL 81,75981.8k $3.9m $3.9m 0.02% —
85 CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 0.01% of their portfolio WEST SACRAMENTO, CA 80,38880.4k $3.8m $3.8m 0.01% —
86 PURA VIDA INVESTMENTS, LLC 0.54% of their portfolio NEW YORK, NY 75,00075.0k $3.6m $3.6m 0.54% —
87 MILLENNIUM MANAGEMENT LLC 0.00% of their portfolio NEW YORK, NY 73,08373.1k $3.5m $3.5m 0.00% —
88 DEUTSCHE BANK AG\ 0.00% of their portfolio FRANKFURT AM MAIN, 2M 72,33772.3k $3.5m $3.5m 0.00% —
89 STATE BOARD OF ADMINISTRATION OF FLORIDA RETIREMENT SYSTEM 0.01% of their portfolio TALLAHASSEE, FL 70,10970.1k $3.4m $3.4m 0.01% —
90 RENAISSANCE TECHNOLOGIES LLC 0.00% of their portfolio NEW YORK, NY 67,40067.4k $3.2m $3.2m 0.00% —
91 CREDIT SUISSE AG/ 0.00% of their portfolio ZURICH, V8 66,97467.0k $3.2m $3.2m 0.00% —
92 VICTORY CAPITAL MANAGEMENT INC 0.00% of their portfolio San Antonio, TX 65,48065.5k $3.1m $3.1m 0.00% —
93 UBS Group AG 0.00% of their portfolio ZURICH, V8 64,94864.9k $3.1m $3.1m 0.00% —
94 NEW YORK STATE TEACHERS RETIREMENT SYSTEM 0.01% of their portfolio ALBANY, NY 64,92064.9k $3.1m $3.1m 0.01% —
95 Thrivent Financial for Lutherans 0.01% of their portfolio Minneapolis, MN 62,14362.1k $3.0m $3.0m 0.01% —
96 KBC Group NV 0.02% of their portfolio Brussels, C9 61,50061.5k $2.9m $2.9m 0.02% —
97 ALGERT GLOBAL LLC 0.18% of their portfolio SAN FRANCISCO, CA 61,18161.2k $2.9m $2.9m 0.18% —
98 SUSQUEHANNA INTERNATIONAL GROUP, LLP 0.01% of their portfolio BALA CYNWYD, PA 58,57958.6k $2.8m $2.8m 0.01% —
99 MUTUAL OF AMERICA CAPITAL MANAGEMENT LLC 0.04% of their portfolio New York, NY 56,56256.6k $2.7m $2.7m 0.04% —
100 BNP PARIBAS FINANCIAL MARKETS 0.01% of their portfolio PARIS, I0 55,37155.4k $2.6m $2.6m 0.01% —