Arrowstreet Capital’s Tandem Diabetes Care TNDM Stock Holding History

Arrowstreet Capital’s Portfolio TNDM Stock Details TNDM Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2026 Q2	$10.1M	Buy	667,689 +474,133	+245%	+$8.28M	﹤0.01%	1070
2026 Q1	$3.71M	Buy	193,556 +57,803	+43%	+$1.26M	﹤0.01%	1246
2025 Q4	$2.98M	Buy	+135,753	New	+$2.45M	﹤0.01%	1278
2025 Q3	–	Sell	-12,411	Closed	-$231K	–	2109
2025 Q2	$231K	Buy	+12,411	New	+$246K	﹤0.01%	1859
2022 Q3	–	Sell	-111,899	Closed	-$6.62M	–	1456
2022 Q2	$6.62M	Buy	111,899 +102,408	+1,079%	+$8.41M	0.01%	560
2022 Q1	$1.1M	Buy	+9,491	New	+$1.11M	﹤0.01%	916
2021 Q2	–	Sell	-98,162	Closed	-$8.66M	–	2221
2021 Q1	$8.66M	Sell	98,162 -16,922	-15%	-$1.57M	0.01%	942
2020 Q4	$11M	Buy	+115,084	New	+$11.9M	0.02%	843
2020 Q1	–	Sell	-92,500	Closed	-$5.51M	–	2115
2019 Q4	$5.51M	Buy	+92,500	New	+$5.7M	0.01%	827

Other funds holding TNDM

BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return

Sessa Capital New York $5.98B AUM 99.85% 1-Year Est. Return

Vanguard Portfolio Management Malvern, Pennsylvania $2.22T AUM

FLAM

First Light Asset Management Edina, Minnesota $1.65B AUM 203.21% 1-Year Est. Return

Vanguard Capital Management Malvern, Pennsylvania $4.68T AUM

State Street Boston, Massachusetts $3.38T AUM 44.17% 1-Year Est. Return

GKIM

GW&K Investment Management Boston, Massachusetts $12.8B AUM 48.82% 1-Year Est. Return

Jennison Associates New York $167B AUM 44.17% 1-Year Est. Return

PIM

Paradice Investment Management Denver, Colorado $627M AUM 43.41% 1-Year Est. Return

Jacobs Levy Equity Management Florham Park, New Jersey $27.8B AUM 46.46% 1-Year Est. Return

Arrowstreet Capital's TNDM Position: Q2 2026 in Review

Arrowstreet Capital increased its Tandem Diabetes Care (TNDM) stake by 245% in Q2 2026, buying an estimated $8.28M and bringing the position to 667,689 shares worth $10.1M. The position accounts for ﹤0.01% of the portfolio, ranked #1070.

Arrowstreet Capital first reported a position in TNDM in Q4 2019 and has held it in 9 quarters since. The position peaked at $11M in Q4 2020. 274 funds tracked by Wall St. Rank hold TNDM as of Q2 2026.

Arrowstreet Capital held 667,689 shares of Tandem Diabetes Care worth $10.1M as of Q2 2026.
Arrowstreet Capital bought 474,133 Tandem Diabetes Care shares in Q2 2026, an estimated $8.28M.
Tandem Diabetes Care made up ﹤0.01% of Arrowstreet Capital's portfolio in Q2 2026, its #1070 holding.
Arrowstreet Capital first reported a position in Tandem Diabetes Care in Q4 2019 and has held it in 9 quarters since.
Arrowstreet Capital's Tandem Diabetes Care position peaked at $11M in Q4 2020.
274 funds tracked by Wall St. Rank held Tandem Diabetes Care as of Q2 2026.

Based on Arrowstreet Capital's 13F filing for Q2 2026, filed 13 Aug 2026.