Tandem Diabetes Care Inc (TNDM) Institutional Ownership

Institutions by Trading Activity

Ownership Statistics

67,652,000Shares Outstanding

76,423,496Shares held by institutions

$1,530,762,625Value of institutional holdings

112.97%Institutional ownership %

6.63%Shares Changed QoQ

259No. of institutional investors

Shares Owned by Institutions

Shares Purchased/Sold by Institutions

Ownership Summary

Tandem Diabetes Care Inc (NASDAQ:TNDM) is held by 259 institutional investors per 13F filings through December 2025.

Their combined ownership stood at 110.4% of outstanding shares in December 2025, down from 112.4% in September 2025.
They increased total shares held in Tandem Diabetes Care by 6.33% from the prior quarter, while the number of investors in TNDM decreased 17.25% year over year.
Activity in TNDM broke down as 131 buyers, 97 sellers, and 31 unchanged among 259 total holders.
Institutional investors collectively held 74.7Mn shares in Tandem Diabetes Care as of December 2025, up by 4.45Mn shares quarter on quarter, and up 811.61K shares year over year.
BlackRock, Inc. is the top holder of Tandem Diabetes Care as of December 31, 2025, with 11.15Mn shares representing 16.48% of outstanding stock.
The largest buyers of Tandem Diabetes Care for the quarter ending December 2025 were CITADEL ADVISORS LLC (2.05Mn), Goldman Sachs Group Inc (1.94Mn), DRIEHAUS CAPITAL MANAGEMENT LLC (1.61Mn), Morgan Stanley (1.34Mn), Assenagon Asset Management S.A. (1.23Mn).
The largest sales of TNDM for the quarter ending December 2025 came from Barclays Plc (1.69Mn), UBS Group AG (1.09Mn), BlackRock, Inc. (952.29K), ArrowMark Colorado Holdings LLC (801.51K), Bank Of America Corp /De/ (614.2K).
Tandem Diabetes Care's 10 largest shareholders as of December 2025 include BlackRock, Inc. (11.15Mn), VANGUARD GROUP INC (7.34Mn), Sessa Capital IM, L.P. (5.0Mn), Goldman Sachs Group Inc (3.37Mn), ArrowMark Colorado Holdings LLC (2.89Mn), GW&K Investment Management, LLC (2.68Mn), State Street Corp (2.64Mn), CITADEL ADVISORS LLC (2.09Mn), Morgan Stanley (2.08Mn), Paradice Investment Management LLC (2.08Mn) per Business Quant data.

259 Institutional Holders

76,423,496 Total Shares Held

Rows:

Download Data

Owner Name	Date	Shares Held	Change (QoQ)	Change (%)	Value (USD)
BlackRock, Inc.	31 Dec, 2025	11,149,181	-952,290	-7.87%	$245,058,999.00
VANGUARD GROUP INC	31 Dec, 2025	7,341,356	278,042	3.94%	$161,363,004.00
Sessa Capital IM, L.P.	31 Dec, 2025	5,000,000	0	0.00%	$109,900,000.00
Goldman Sachs Group Inc	31 Dec, 2025	3,366,800	1,935,428	135.21%	$74,002,266.00
ArrowMark Colorado Holdings LLC	31 Dec, 2025	2,889,691	-801,507	-21.71%	$63,515,408.00
GW&K Investment Management, LLC	31 Dec, 2025	2,675,157	-46,492	-1.71%	$58,800.00
State Street Corp	31 Dec, 2025	2,641,724	-26,464	-0.99%	$58,065,094.00
CITADEL ADVISORS LLC	31 Dec, 2025	2,088,603	2,048,802	5,147.61%	$45,907,494.00
Morgan Stanley	31 Dec, 2025	2,080,497	1,342,950	182.08%	$45,729,350.00
Paradice Investment Management LLC	31 Dec, 2025	2,077,745	-118,723	-5.41%	$45,668,835.00
JENNISON ASSOCIATES LLC	31 Dec, 2025	2,021,376	601,260	42.34%	$44,429,844.00
JACOBS LEVY EQUITY MANAGEMENT, INC	31 Dec, 2025	1,653,708	171,755	11.59%	$36,348,502.00
GEODE CAPITAL MANAGEMENT, LLC	31 Dec, 2025	1,649,383	51,102	3.20%	$36,259,526.00
DRIEHAUS CAPITAL MANAGEMENT LLC	31 Dec, 2025	1,610,342	1,610,342	0.00%	$35,395,317.00
Freestone Grove Partners LP	31 Dec, 2025	1,442,836	-427,471	-22.86%	$31,713,535.00
BNP PARIBAS FINANCIAL MARKETS	31 Dec, 2025	1,248,481	1,028,866	468.49%	$27,441,612.00
Assenagon Asset Management S.A.	31 Dec, 2025	1,227,856	1,227,856	0.00%	$26,988,275.00
TWO SIGMA INVESTMENTS, LP	31 Dec, 2025	1,201,527	84,325	7.55%	$26,409,563.00
BAILLIE GIFFORD & CO	31 Dec, 2025	1,145,516	24,921	2.22%	$25,178,442.00
First Light Asset Management, LLC	31 Dec, 2025	1,089,493	1,089,493	0.00%	$23,947,056.00

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