Marshall Wace
TNDM icon

Marshall Wace’s Tandem Diabetes Care TNDM Stock Holding History

Marshall Wace’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
Q1 		$27.7M Buy
1,442,472
+566,941
+65% +$12.3M 0.03% 584
2025
Q4 		$19.2M Buy
+875,531
New +$15.8M 0.02% 640
2025
Q2 		– Sell
-70,399
Closed -$1.35M – 3176
2025
Q1 		$1.35M Sell
70,399
-880,549
-93% -$25.8M ﹤0.01% 1652
2024
Q4 		$34.3M Buy
950,948
+137,354
+17% +$4.65M 0.04% 381
2024
Q3 		$34.5M Buy
813,594
+289,201
+55% +$12.3M 0.04% 362
2024
Q2 		$21.1M Sell
524,393
-2,595,981
-83% -$108M 0.03% 480
2024
Q1 		$110M Buy
3,120,374
+2,768,459
+787% +$74.2M 0.17% 113
2023
Q4 		$10.4M Buy
351,915
+172,875
+97% +$3.59M 0.02% 680
2023
Q3 		$3.72M Sell
179,040
-478,121
-73% -$13.1M 0.01% 982
2023
Q2 		$16.1M Buy
+657,161
New +$21.1M 0.03% 555
2023
Q1 		– Sell
-881,307
Closed -$39.6M – 3106
2022
Q4 		$39.6M Buy
+881,307
New +$39.9M 0.09% 247
2022
Q2 		– Sell
-24,703
Closed -$2.87M – 3845
2022
Q1 		$2.87M Sell
24,703
-55,673
-69% -$6.5M 0.01% 1821
2021
Q4 		$12.1M Buy
80,376
+64,572
+409% +$8.72M 0.02% 733
2021
Q3 		$1.89M Buy
+15,804
New +$1.74M 0.01% 1606
2021
Q2 		– Sell
-4,795
Closed -$424K – 3095
2021
Q1 		$424K Buy
4,795
+646
+16% +$60K ﹤0.01% 2005
2020
Q4 		$397K Sell
4,149
-9,184
-69% -$946K ﹤0.01% 1575
2020
Q3 		$1.51M Buy
13,333
+3,443
+35% +$362K 0.01% 888
2020
Q2 		$978K Buy
+9,890
New +$789K 0.01% 1001
2020
Q1 		– Sell
-5,140
Closed -$306K – 2061
2019
Q4 		$306K Sell
5,140
-3,433
-40% -$212K ﹤0.01% 1274
2019
Q3 		$506K Buy
8,573
+2,839
+50% +$181K ﹤0.01% 1106
2019
Q2 		$370K Buy
+5,734
New +$370K ﹤0.01% 1138
2019
Q1 		– Sell
-14,699
Closed -$558K – 2059
2018
Q4 		$558K Buy
+14,699
New +$519K 0.01% 1064

Other funds holding TNDM

BlackRock
BlackRock New York $5.72T AUM 30.48% 1-Year Est. Return
SC
Sessa Capital New York $5.51B AUM 47.23% 1-Year Est. Return
VPM
Vanguard Portfolio Management Malvern, Pennsylvania $1.91T AUM
ACH
ArrowMark Colorado Holdings Denver, Colorado $3.76B AUM 21.77% 1-Year Est. Return
VCM
Vanguard Capital Management Malvern, Pennsylvania $4.04T AUM
GKIM
GW&K Investment Management Boston, Massachusetts $11.3B AUM 31.98% 1-Year Est. Return
State Street
State Street Boston, Massachusetts $2.9T AUM 29.55% 1-Year Est. Return
DCM
Driehaus Capital Management Chicago, Illinois $13.6B AUM 173.98% 1-Year Est. Return
Goldman Sachs
Goldman Sachs New York $871B AUM 31.28% 1-Year Est. Return
Citadel Advisors
Citadel Advisors Miami, Florida $618B AUM 30.34% 1-Year Est. Return

Marshall Wace's TNDM Position: Q1 2026 in Review

Marshall Wace increased its Tandem Diabetes Care (TNDM) stake by 65% in Q1 2026, buying an estimated $12.3M and bringing the position to 1,442,472 shares worth $27.7M. The position accounts for 0.03% of the portfolio, ranked #584.

Marshall Wace first reported a position in TNDM in Q4 2018 and has held it in 22 quarters since. The position peaked at $110M in Q1 2024. 272 funds tracked by Wall St. Rank hold TNDM as of Q1 2026.

  • Marshall Wace held 1,442,472 shares of Tandem Diabetes Care worth $27.7M as of Q1 2026.
  • Marshall Wace bought 566,941 Tandem Diabetes Care shares in Q1 2026, an estimated $12.3M.
  • Tandem Diabetes Care made up 0.03% of Marshall Wace's portfolio in Q1 2026, its #584 holding.
  • Marshall Wace first reported a position in Tandem Diabetes Care in Q4 2018 and has held it in 22 quarters since.
  • Marshall Wace's Tandem Diabetes Care position peaked at $110M in Q1 2024.
  • 272 funds tracked by Wall St. Rank held Tandem Diabetes Care as of Q1 2026.

Based on Marshall Wace's 13F filing for Q1 2026, filed 15 May 2026.