Tandem Diabetes Care TNDM Institutional Ownership

NASDAQ TNDM

$18.96 -0.15 (-0.78%)

As of: Sep 10, 2026 · 9:58 AM EDT

Institutions by Trading Activity

275 Institutions

Increased 146 53.1%

Unchanged 40 14.5%

Reduced 89 32.4%

Ownership Statistics

13F · as of 30 Jun, 2026

Institutional Ownership

115.04%

▼-0.03 pp QoQ

Shares Held by Institutions

79.39Mn

of 69.01Mn outstanding

▲+6.98% QoQ

Shares Outstanding

69.01Mn

-10.38Mn held outside 13F filers

Institutional Investors

275

filed 13F for Jun 2026

▲+2 vs prior quarter

Net Shares Added (QoQ)

+5.18Mn

accumulated since last quarter

Value of Holdings

$1.58Bn

reported market value

Shares Owned by Institutions

Shares held % of outstanding

Latest —

Average ownership —

Peak ownership —

Shares Purchased/Sold by Institutions

Accumulated Distributed

Latest quarter —

Net over range —

Accumulating quarters —

Ownership Summary

Quarter ending 30 Jun, 2026

Tandem Diabetes Care Inc (NASDAQ:TNDM) is held by 275 institutional investors per 13F filings through June 2026.

Collectively, these holders controlled 115.0% of Tandem Diabetes Care's outstanding shares in June 2026, down from 115.1% in March 2026.
They increased total shares held in Tandem Diabetes Care by 6.98% from last quarter, and the number of investors in TNDM increased 2.23% annually.
During the quarter, 146 of these 275 funds increased positions in TNDM, 89 reduced exposure, and 40 held steady.
The aggregate institutional position in Tandem Diabetes Care amounted to 79.39Mn shares as of June 2026, up by 5.18Mn shares quarter on quarter, and down 1.86Mn shares year over year.
As of June 30, 2026, BlackRock, Inc. held the largest stake in Tandem Diabetes Care with 11.58Mn shares, accounting for 16.78% of total shares outstanding.
The most significant purchases of TNDM for the quarter ending June 2026 came from First Light Asset Management, LLC (2.07Mn), Woodline Partners LP (1.31Mn), BlackRock, Inc. (892.28K), JENNISON ASSOCIATES LLC (672.98K), Sixth Street Partners Management Company, L.P. (656.84K).
The largest sellers of Tandem Diabetes Care for the quarter ending June 2026 were ArrowMark Colorado Holdings LLC (1.8Mn), Goldman Sachs Group Inc (1.36Mn), TWO SIGMA INVESTMENTS, LP (1.31Mn), UBS Group AG (901.22K), Morgan Stanley (710.47K).
Business Quant data shows the 10 biggest positions in Tandem Diabetes Care as of June 2026 are held by BlackRock, Inc. (11.58Mn), Sessa Capital IM, L.P. (5.1Mn), VANGUARD PORTFOLIO MANAGEMENT LLC (4.3Mn), First Light Asset Management, LLC (3.38Mn), VANGUARD CAPITAL MANAGEMENT LLC (3.1Mn), State Street Corp (2.85Mn), GW&K Investment Management, LLC (2.57Mn), JENNISON ASSOCIATES LLC (2.33Mn), Paradice Investment Management LLC (2.02Mn), JACOBS LEVY EQUITY MANAGEMENT, INC (2.01Mn).

Form 13F Holdings

275 Institutional Holders

Report period 30 Jun, 2026

Total shares held 79.39Mn

Of outstanding 115.04%

#	Institution	CIK	Shares Held	% of Outstanding	Change (QoQ)	Change (%)	Value (USD)
1	BlackRock, Inc.	0002012383	11,583,125	16.78%	▲892,281	+8.35%	$174.79Mn
2	Sessa Capital IM, L.P.	0001595849	5,100,000	7.39%	▲369,243	+7.81%	$76.96Mn
3	VANGUARD PORTFOLIO MANAGEMENT LLC	0002100121	4,299,667	6.23%	▲306,334	+7.67%	$64.88Mn
4	First Light Asset Management, LLC	0001600004	3,383,553	4.90%	▲2,068,838	+157.36%	$51.06Mn
5	VANGUARD CAPITAL MANAGEMENT LLC	0002100119	3,096,536	4.49%	▲57,617	+1.90%	$46.73Mn
6	State Street Corp	0000093751	2,851,646	4.13%	▲189,386	+7.11%	$43.03Mn
7	GW&K Investment Management, LLC	0001082917	2,569,032	3.72%	▼120,074	-4.47%	$38.77K
8	JENNISON ASSOCIATES LLC	0000053417	2,331,429	3.38%	▲672,981	+40.58%	$35.18Mn
9	Paradice Investment Management LLC	0001620275	2,024,014	2.93%	▼18,411	-0.90%	$30.54Mn
10	JACOBS LEVY EQUITY MANAGEMENT, INC	0000884414	2,006,429	2.91%	▲482,483	+31.66%	$30.28Mn
11	Freestone Grove Partners LP	0002007591	1,866,134	2.70%	▲535,392	+40.23%	$28.16Mn
12	GEODE CAPITAL MANAGEMENT, LLC	0001214717	1,800,797	2.61%	▲120,934	+7.20%	$27.18Mn
13	DRIEHAUS CAPITAL MANAGEMENT LLC	0000938206	1,786,996	2.59%	▼517,418	-22.45%	$26.97Mn
14	CITADEL ADVISORS LLC	0001423053	1,735,879	2.52%	▼456,788	-20.83%	$26.19Mn
15	MILLENNIUM MANAGEMENT LLC	0001273087	1,311,739	1.90%	▲550,067	+72.22%	$19.79Mn
16	Woodline Partners LP	0001784547	1,307,439	1.89%	▲1,307,439	0.00%	$19.73Mn
17	ArrowMark Colorado Holdings LLC	0001483859	1,299,586	1.88%	▼1,804,023	-58.13%	$19.61Mn
18	UBS Group AG	0001610520	1,146,580	1.66%	▼901,221	-44.01%	$17.30Mn
19	FMR LLC	0000315066	976,432	1.41%	▲262,421	+36.75%	$14.73Mn
20	ROYCE & ASSOCIATES LP	0000906304	900,590	1.30%	▲204,000	+29.29%	$13.59Mn

Showing 1 to 20 of 275 holders