Security Snapshot

TANDEM DIABETES CARE INC - Common Stock (TNDM) Institutional Ownership

CUSIP: 875372203

13F Institutional Holders and Ownership History from Q1 2016 to Q1 2026

Latest Period

Q4 2025

Institutions Reporting

267

Shares (Excl. Options)

74,865,534

Price

$21.98

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Type / Class
Equity / Common Stock
Symbol
TNDM on Nasdaq
Shares outstanding
68,605,637
Price per share
$18.28
All holders as of 31 Dec 2025
Q4 2025
Total 13F shares
74,865,534
Total reported value
$1,645,500,988
% of total 13F portfolios
0%
Share change
-507,386
Value change
+$37,201,261
Number of holders
267
Price from insider filings
$18.28
Reported Shares, Excluding Options vs Price
Reported Value, Excluding Options
Total Investors

Quick Takeaways

  • TNDM - TANDEM DIABETES CARE INC - Common Stock is tracked under CUSIP 875372203.
  • 267 institutions reported positions in Q4 2025.
  • 5 significant owners is listed from Schedule 13D/13G reporting.

What Changed

  • Holder count moved from 267 to 66 between Q4 2025 and Q1 2026.
  • Reported value moved from $1,645,500,988 to $34,314,236.

Why This Matters

  • You can quickly see who holds this security, then open quarter and manager detail pages for full evidence.
  • 13F and Schedule 13D/13G sections are kept together so you can cross-check institutional and beneficial ownership context.

Source Evidence

Source: SEC Form 13F

Latest holder context comes from 267 institutions filings for Q4 2025.

Open SEC Evidence

Investment Quick Answers

What is CUSIP 875372203?
CUSIP 875372203 identifies TNDM - TANDEM DIABETES CARE INC - Common Stock in SEC 13F datasets.

Where can I see the latest institutional holders?
Review the Q4 2025 holders report and the ownership history table below.

Significant Owners of TANDEM DIABETES CARE INC - Common Stock (TNDM) based on Schedule 13D/G filings

Filer Ownership Change % Holdings Value Net Change Nb Shares Change % Reporting Name Report Period
BlackRock, Inc. 15% $176,563,735 10,106,682 BlackRock, Inc. 31 Mar 2025
Sessa Capital (Master), L.P. 6.7% $78,026,383 4,466,307 Sessa Capital (Master), L.P. 31 Mar 2025
VANGUARD PORTFOLIO MANAGEMENT LLC 5.9% $77,682,093 4,052,274 Vanguard Portfolio Management 31 Mar 2026
VANGUARD CAPITAL MANAGEMENT LLC 5.2% $68,125,809 3,553,772 Vanguard Capital Management 31 Mar 2026
ArrowMark Colorado Holdings LLC 4.3% -24% $62,272,841 -$17,272,476 2,889,691 -22% ArrowMark Colorado Holdings, LLC 31 Dec 2025

As of 31 Dec 2025, 267 institutional investors reported holding 74,865,534 shares of TANDEM DIABETES CARE INC - Common Stock (TNDM). This represents 109% of the company’s total 68,605,637 outstanding shares.

Top 25 Institutional Shareholders

The largest institutional shareholders of TANDEM DIABETES CARE INC - Common Stock (TNDM) together control 85% of the company’s outstanding shares — a level of ownership often associated with strong institutional conviction and long‑term capital commitment.

Institution Ownership % Shares Held Share Change % Portfolio % Holdings Value
BlackRock, Inc. 16% 11,149,181 -7.9% 0% $245,058,999
VANGUARD GROUP INC 11% 7,341,356 +3.9% 0% $161,363,004
Sessa Capital IM, L.P. 7.3% 5,000,000 0% 2.2% $109,900,000
ArrowMark Colorado Holdings LLC 4.2% 2,889,691 -22% 1.4% $63,515,408
GW&K Investment Management, LLC 3.9% 2,675,157 -1.7% 0.51% $58,800,000
STATE STREET CORP 3.9% 2,641,724 -0.99% 0% $58,065,094
CITADEL ADVISORS LLC 3% 2,088,603 +5148% 0.03% $45,907,494
MORGAN STANLEY 3% 2,080,497 +182% 0% $45,729,350
Paradice Investment Management LLC 3% 2,077,745 -5.4% 8.9% $45,668,835
JENNISON ASSOCIATES LLC 2.9% 2,021,376 +42% 0.03% $44,429,844
GOLDMAN SACHS GROUP INC 2.5% 1,683,400 +18% 0.01% $37,001,133
JACOBS LEVY EQUITY MANAGEMENT, INC 2.4% 1,653,708 +12% 0.14% $36,348,502
GEODE CAPITAL MANAGEMENT, LLC 2.4% 1,649,383 +3.2% 0% $36,259,526
Driehaus Capital Management LLC 2.3% 1,610,342 0.24% $35,395,317
Freestone Grove Partners LP 2.1% 1,442,836 -23% 0.23% $31,713,535
BNP PARIBAS FINANCIAL MARKETS 1.8% 1,248,481 0% 0.02% $27,441,612
Assenagon Asset Management S.A. 1.8% 1,227,856 0.04% $26,988,275
TWO SIGMA INVESTMENTS, LP 1.8% 1,201,527 +7.5% 0.04% $26,409,563
BAILLIE GIFFORD & CO 1.7% 1,145,516 +2.2% 0.02% $25,178,442
First Light Asset Management, LLC 1.6% 1,089,493 1.8% $23,947,056
TWO SIGMA ADVISERS, LP 1.4% 937,983 -3.4% 0.04% $20,616,866
BARCLAYS PLC 1.3% 917,927 -23% 0.01% $20,176,036
MARSHALL WACE, LLP 1.3% 875,531 0.02% $19,244,172
D. E. Shaw & Co., Inc. 1.2% 854,266 -2.6% 0.01% $18,776,767
BANK OF AMERICA CORP /DE/ 1% 702,503 +6.7% 0% $15,441,016

Institutional Holders of TANDEM DIABETES CARE INC - Common Stock (TNDM) across Reporting Periods

Period Reported Shares, Excl. Options Value, Excl. Options Value Change Price (Median) Investors
2026 Q1 1,790,742 $34,314,236 -$28,713,651 $19.17 66
2025 Q4 74,865,534 $1,645,500,988 +$37,201,261 $21.98 267
2025 Q3 75,062,169 $911,087,579 -$138,652,756 $12.14 251
2025 Q2 80,970,548 $1,506,919,626 +$146,515,993 $18.64 269
2025 Q1 73,028,420 $1,399,471,204 -$74,262,859 $19.16 271
2024 Q4 72,082,680 $2,596,593,509 -$54,203,387 $36.02 311
2024 Q3 73,070,303 $3,098,544,283 -$23,063,732 $42.41 326
2024 Q2 73,624,715 $2,966,330,226 -$12,633,640 $40.29 315
2024 Q1 74,163,562 $2,626,695,815 +$150,901,685 $35.41 290
2023 Q4 70,841,842 $2,095,507,190 +$47,113,352 $29.58 264
2023 Q3 69,587,644 $1,445,242,152 +$40,169,385 $20.77 224
2023 Q2 67,061,755 $1,645,737,206 -$59,226,945 $24.54 242
2023 Q1 68,103,120 $2,765,613,824 +$144,781,126 $40.61 270
2022 Q4 64,356,332 $2,890,283,528 +$83,553,842 $44.95 290
2022 Q3 62,774,623 $3,005,075,951 -$3,660,996 $47.85 279
2022 Q2 61,447,968 $3,637,020,281 -$76,699,636 $59.19 317
2022 Q1 59,516,284 $6,922,056,028 -$138,240,750 $116.29 365
2021 Q4 60,391,589 $9,087,447,171 -$2,104,121 $150.52 376
2021 Q3 61,294,210 $7,318,019,845 +$274,585,725 $119.38 331
2021 Q2 59,035,893 $5,750,025,560 +$205,481,616 $97.40 295
2021 Q1 57,554,702 $5,079,400,953 -$46,897,671 $88.25 282
2020 Q4 58,469,670 $5,594,436,203 +$259,885,627 $95.68 295
2020 Q3 54,610,664 $6,195,906,490 -$74,521,157 $113.50 317
2020 Q2 55,340,731 $5,467,195,169 +$30,463,584 $98.92 298
2020 Q1 55,943,514 $3,597,678,709 +$179,201,893 $64.35 272
2019 Q4 54,323,826 $3,238,388,302 +$215,522,474 $59.61 277
2019 Q3 49,570,173 $2,923,699,368 +$150,187,596 $58.98 265
2019 Q2 46,969,436 $3,030,219,186 +$32,868,289 $64.52 257
2019 Q1 46,852,382 $2,975,069,325 -$42,975,705 $63.50 259
2018 Q4 47,679,245 $1,810,642,238 +$238,092,658 $37.97 197
2018 Q3 41,283,497 $1,768,571,420 +$363,867,902 $42.84 180
2018 Q2 33,358,770 $734,537,970 +$323,358,099 $22.02 114
2018 Q1 21,326,200 $105,775,575 +$86,906,889 $4.96 72
2017 Q4 1,658,886 $3,911,007 -$15,365,244 $2.36 29
2017 Q3 8,179,498 $5,969,000 +$5,969,000 $0.73 4
2016 Q2 0 $0 -$10,000 $18.28 0
2016 Q1 150 $10,000 $66.67 1
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