Dimensional Fund Advisors
MASI

Dimensional Fund Advisors’s Masimo MASI Stock Holding History

Dimensional Fund Advisors’s Portfolio MASI Stock Details MASI Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q1 		$29.2M Sell
164,402
-9,548
-5% -$1.5M 0.01% 1781
2025
Q4 		$22.6M Sell
173,950
-85,718
-33% -$12.3M ﹤0.01% 1910
2025
Q3 		$38.3M Sell
259,668
-263,558
-50% -$39.9M 0.01% 1661
2025
Q2 		$88M Sell
523,226
-180,152
-26% -$28.8M 0.02% 1119
2025
Q1 		$117M Buy
703,378
+55,658
+9% +$9.66M 0.03% 841
2024
Q4 		$107M Buy
647,720
+50,022
+8% +$7.9M 0.03% 966
2024
Q3 		$79.7M Buy
597,698
+72,104
+14% +$8.37M 0.02% 1204
2024
Q2 		$66.2M Buy
525,594
+165,257
+46% +$21.8M 0.02% 1267
2024
Q1 		$52.9M Buy
360,337
+58,849
+20% +$7.6M 0.01% 1416
2023
Q4 		$35.3M Buy
301,488
+16,042
+6% +$1.5M 0.01% 1670
2023
Q3 		$25M Buy
285,446
+29,997
+12% +$3.49M 0.01% 1802
2023
Q2 		$42M Buy
255,449
+17,574
+7% +$3.06M 0.01% 1479
2023
Q1 		$43.9M Buy
237,875
+9,213
+4% +$1.55M 0.01% 1427
2022
Q4 		$33.8K Buy
228,662
+3,375
+1% +$464K 0.01% 1573
2022
Q3 		$31.8M Buy
225,287
+11,308
+5% +$1.65M 0.01% 1551
2022
Q2 		$28M Sell
213,979
-12,547
-6% -$1.68M 0.01% 1679
2022
Q1 		$33M Buy
226,526
+8,501
+4% +$1.63M 0.01% 1685
2021
Q4 		$63.8M Sell
218,025
-407
-0.2% -$116K 0.02% 1239
2021
Q3 		$59.1M Sell
218,432
-15,099
-6% -$4.09M 0.02% 1269
2021
Q2 		$56.6M Sell
233,531
-7,718
-3% -$1.76M 0.02% 1336
2021
Q1 		$55.4M Buy
241,249
+10,801
+5% +$2.71M 0.02% 1362
2020
Q4 		$61.8M Sell
230,448
-10,893
-5% -$2.72M 0.02% 1184
2020
Q3 		$57M Sell
241,341
-11,492
-5% -$2.58M 0.02% 1084
2020
Q2 		$57.6M Sell
252,833
-10,084
-4% -$2.21M 0.03% 1079
2020
Q1 		$46.6M Sell
262,917
-31,971
-11% -$5.48M 0.02% 1087
2019
Q4 		$46.6M Sell
294,888
-16,863
-5% -$2.53M 0.02% 1507
2019
Q3 		$46.4M Sell
311,751
-78,481
-20% -$11.9M 0.02% 1454
2019
Q2 		$58.1M Sell
390,232
-2,687
-0.7% -$369K 0.02% 1276
2019
Q1 		$54.3M Buy
392,919
+45
+0% +$5.65K 0.02% 1316
2018
Q4 		$42.2M Sell
392,874
-16,352
-4% -$1.82M 0.02% 1439
2018
Q3 		$51M Sell
409,226
-8,349
-2% -$926K 0.02% 1444
2018
Q2 		$40.8M Sell
417,575
-66,563
-14% -$6.33M 0.02% 1628
2018
Q1 		$42.6M Sell
484,138
-25,442
-5% -$2.22M 0.02% 1508
2017
Q4 		$43.2M Sell
509,580
-117,351
-19% -$10.2M 0.02% 1513
2017
Q3 		$54.3M Sell
626,931
-75,215
-11% -$6.65M 0.02% 1215
2017
Q2 		$64M Sell
702,146
-391,059
-36% -$35.9M 0.03% 942
2017
Q1 		$102M Sell
1,093,205
-43,194
-4% -$3.56M 0.05% 517
2016
Q4 		$76.6M Sell
1,136,399
-11,957
-1% -$735K 0.04% 686
2016
Q3 		$68.3M Buy
1,148,356
+15,562
+1% +$878K 0.04% 723
2016
Q2 		$59.5M Sell
1,132,794
-38,486
-3% -$1.81M 0.03% 786
2016
Q1 		$49M Sell
1,171,280
-179,932
-13% -$6.77M 0.03% 945
2015
Q4 		$56.1M Buy
1,351,212
+76,849
+6% +$3.14M 0.04% 742
2015
Q3 		$49.1M Buy
1,274,363
+32,032
+3% +$1.31M 0.03% 818
2015
Q2 		$48.1M Buy
1,242,331
+76,693
+7% +$2.75M 0.03% 900
2015
Q1 		$38.4M Buy
1,165,638
+91,968
+9% +$2.64M 0.02% 1112
2014
Q4 		$28.3M Buy
1,073,670
+109,557
+11% +$2.7M 0.02% 1365
2014
Q3 		$20.5M Buy
964,113
+48,017
+5% +$1.1M 0.01% 1612
2014
Q2 		$21.6M Buy
916,096
+123,023
+16% +$3.05M 0.02% 1584
2014
Q1 		$21.7M Buy
793,073
+84,034
+12% +$2.4M 0.02% 1497
2013
Q4 		$20.7M Buy
709,039
+60,283
+9% +$1.69M 0.02% 1514
2013
Q3 		$17.3M Buy
648,756
+93,409
+17% +$2.3M 0.02% 1593
2013
Q2 		$11.8M Buy
+555,347
New +$11.7M 0.01% 1866

Other funds holding MASI

BlackRock
BlackRock New York $5.72T AUM 30.48% 1-Year Est. Return
PCM
Politan Capital Management New York $985M AUM 3.12% 1-Year Est. Return
PCM
Pentwater Capital Management Naples, Florida $19.3B AUM 58.13% 1-Year Est. Return
Barclays
Barclays London, United Kingdom $416B AUM 33.63% 1-Year Est. Return
HI
HBK Investments Dallas, Texas $9.85B AUM 55.6% 1-Year Est. Return
Massachusetts Financial Services
Massachusetts Financial Services Boston, Massachusetts $298B AUM 21.96% 1-Year Est. Return
VCM
Vanguard Capital Management Malvern, Pennsylvania $4.04T AUM
VPM
Vanguard Portfolio Management Malvern, Pennsylvania $1.91T AUM
Fidelity Investments
Fidelity Investments Boston, Massachusetts $1.9T AUM 41.92% 1-Year Est. Return
State Street
State Street Boston, Massachusetts $2.9T AUM 29.55% 1-Year Est. Return

Dimensional Fund Advisors's MASI Position: Q1 2026 in Review

Dimensional Fund Advisors reduced its Masimo (MASI) stake by 5.5% in Q1 2026, selling an estimated $1.5M and leaving 164,402 shares worth $29.2M. The position accounts for 0.01% of the portfolio, ranked #1781.

Dimensional Fund Advisors first reported a position in MASI in Q2 2013 and has held it in 52 quarters since. The position peaked at $117M in Q1 2025. 445 funds tracked by Wall St. Rank hold MASI as of Q1 2026.

  • Dimensional Fund Advisors held 164,402 shares of Masimo worth $29.2M as of Q1 2026.
  • Dimensional Fund Advisors sold 9,548 Masimo shares in Q1 2026, an estimated $1.5M.
  • Masimo made up 0.01% of Dimensional Fund Advisors's portfolio in Q1 2026, its #1781 holding.
  • Dimensional Fund Advisors first reported a position in Masimo in Q2 2013 and has held it in 52 quarters since.
  • Dimensional Fund Advisors's Masimo position peaked at $117M in Q1 2025.
  • 445 funds tracked by Wall St. Rank held Masimo as of Q1 2026.

Based on Dimensional Fund Advisors's 13F filing for Q1 2026, filed 7 May 2026.