Tandem Diabetes Care Inc (TNDM) Institutional Ownership

Institutions by Trading Activity

Ownership Statistics

0Shares Outstanding

2,368,833Shares held by institutions

$46,417,283Value of institutional holdings

121.16%Institutional ownership %

12.90%Shares Changed QoQ

268No. of institutional investors

Shares Owned by Institutions

Shares Purchased/Sold by Institutions

Ownership Summary

Tandem Diabetes Care Inc (NASDAQ:TNDM) has 259 institutional investors with active 13F positions as of December 2025.

These investors collectively held 110.4% of Tandem Diabetes Care's outstanding shares in December 2025, down from 112.4% in September 2025.
Their total shares held in TNDM increased 6.33% quarter over quarter, and separately, investors owning Tandem Diabetes Care decreased 17.25% from a year ago.
Of these 259 holders, 131 added to their stakes in Tandem Diabetes Care, 97 trimmed positions, and 31 made no changes.
In total, institutional investors 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. leads ownership in TNDM with 11.15Mn shares as of December 31, 2025, equal to 16.48% of outstanding shares.
Leading buyers of Tandem Diabetes Care shares for the quarter ending December 2025 were CITADEL ADVISORS LLC (2.05Mn), DRIEHAUS CAPITAL MANAGEMENT LLC (1.61Mn), Morgan Stanley (1.34Mn), Assenagon Asset Management S.A. (1.23Mn), First Light Asset Management, LLC (1.09Mn).
Top sellers of TNDM stock for the quarter ending December 2025 included UBS Group AG (1.09Mn), BlackRock, Inc. (952.29K), ArrowMark Colorado Holdings LLC (801.51K), Bank Of America Corp /De/ (614.2K), ACADIAN ASSET MANAGEMENT LLC (525.96K).
Per Business Quant, the top 10 investors in TNDM for the quarter ending December 2025 include BlackRock, Inc. (11.15Mn), VANGUARD GROUP INC (7.34Mn), Sessa Capital IM, L.P. (5.0Mn), 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), JENNISON ASSOCIATES LLC (2.02Mn).

259 Institutional Holders

2,368,833 Total Shares Held

Rows:

Download Data

Owner Name	Date	Change (QoQ)	Change (%)	Value (USD)
BlackRock, Inc.	31 Dec, 2025	-952,290	-7.87%	$0.00
VANGUARD GROUP INC	31 Dec, 2025	278,042	3.94%	$0.00
Paradice Investment Management LLC	31 Dec, 2025	-118,723	-5.41%	$0.00
Barclays Plc	31 Dec, 2025	-503,265	-35.41%	$0.00
Sessa Capital IM, L.P.	31 Dec, 2025	0	0.00%	$0.00
Freestone Grove Partners LP	31 Dec, 2025	-427,471	-22.86%	$0.00
HSBC HOLDINGS PLC	31 Dec, 2025	-19,820	-21.33%	$0.00
ArrowMark Colorado Holdings LLC	31 Dec, 2025	-801,507	-21.71%	$0.00
Nuveen, LLC	31 Dec, 2025	60,664	12.07%	$0.00
Rockefeller Capital Management L.P.	31 Dec, 2025	852	211.94%	$0.00
GW&K Investment Management, LLC	31 Dec, 2025	-46,492	-1.71%	$0.00
Aberdeen Group plc	31 Dec, 2025	-51,061	-8.54%	$0.00
State Street Corp	31 Dec, 2025	-26,464	-0.99%	$0.00
UBS Group AG	31 Dec, 2025	-1,086,544	-72.23%	$0.00
CITADEL ADVISORS LLC	31 Dec, 2025	2,048,802	5,147.61%	$0.00
Quantinno Capital Management LP	31 Dec, 2025	91,716	45.68%	$0.00
Morgan Stanley	31 Dec, 2025	1,342,950	182.08%	$0.00
EDMOND DE ROTHSCHILD HOLDING S.A.	31 Dec, 2025	-75,000	-22.51%	$0.00
JENNISON ASSOCIATES LLC	31 Dec, 2025	601,260	42.34%	$0.00
MIZUHO MARKETS AMERICAS LLC	31 Dec, 2025	27,255	23.22%	$0.00

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