Jane Street
MASI

Jane Street’s Masimo MASI Stock Holding History

Jane Street’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 		$1.51M Buy
8,500
+5,700
+204% +$895K ﹤0.01% 5623
2025
Q4 		$364K Sell
2,800
-1,400
-33% -$200K ﹤0.01% 8401
2025
Q3 		$620K Buy
4,200
+1,300
+45% +$197K ﹤0.01% 7383
2025
Q2 		$488K Buy
+2,900
New +$463K ﹤0.01% 6964
2025
Q1 		– Sell
-9,300
Closed -$1.54M – 10134
2024
Q4 		$1.54M Sell
9,300
-19,300
-67% -$3.05M ﹤0.01% 4591
2024
Q3 		$3.81M Buy
28,600
+4,200
+17% +$487K ﹤0.01% 3304
2024
Q2 		$3.07M Buy
24,400
+16,500
+209% +$2.17M ﹤0.01% 3774
2024
Q1 		$1.16M Sell
7,900
-63,800
-89% -$8.24M ﹤0.01% 5130
2023
Q4 		$8.4M Buy
71,700
+6,800
+10% +$634K ﹤0.01% 2165
2023
Q3 		$5.69M Buy
64,900
+58,100
+854% +$6.76M ﹤0.01% 2433
2023
Q2 		$1.12M Buy
6,800
+1,300
+24% +$226K ﹤0.01% 5032
2023
Q1 		$1.01M Buy
5,500
+3,800
+224% +$641K ﹤0.01% 4967
2022
Q4 		$252K Sell
1,700
-10,400
-86% -$1.43M ﹤0.01% 7312
2022
Q3 		$1.71M Buy
12,100
+10,500
+656% +$1.53M ﹤0.01% 4468
2022
Q2 		$209K Sell
1,600
-26,300
-94% -$3.52M ﹤0.01% 8144
2022
Q1 		$4.06M Sell
27,900
-97,900
-78% -$18.8M ﹤0.01% 3399
2021
Q4 		$36.8M Buy
125,800
+67,800
+117% +$19.3M 0.01% 802
2021
Q3 		$15.7M Buy
58,000
+47,900
+474% +$13M 0.01% 1315
2021
Q2 		$2.45M Sell
10,100
-56,200
-85% -$12.8M ﹤0.01% 3938
2021
Q1 		$15.2M Buy
66,300
+61,600
+1,311% +$15.5M 0.01% 1194
2020
Q4 		$1.26M Sell
4,700
-32,200
-87% -$8.03M ﹤0.01% 4284
2020
Q3 		$8.71M Sell
36,900
-46,600
-56% -$10.4M 0.01% 1326
2020
Q2 		$19M Buy
+83,500
New +$18.3M 0.01% 786

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

Jane Street's MASI Position: Q1 2026 in Review

Jane Street reduced its Masimo (MASI) stake by 99% in Q1 2026, selling an estimated $16M and leaving 1,215 shares worth $216K. The position accounts for ﹤0.01% of the portfolio, ranked #9974.

Jane Street first reported a position in MASI in Q3 2013 and has held it in 36 quarters since. The position peaked at $18.2M in Q3 2022. 445 funds tracked by Wall St. Rank hold MASI as of Q1 2026.

  • Jane Street held 1,215 shares of Masimo worth $216K as of Q1 2026.
  • Jane Street sold 101,666 Masimo shares in Q1 2026, an estimated $16M.
  • Masimo made up ﹤0.01% of Jane Street's portfolio in Q1 2026, its #9974 holding.
  • Jane Street first reported a position in Masimo in Q3 2013 and has held it in 36 quarters since.
  • Jane Street's Masimo position peaked at $18.2M in Q3 2022.
  • 445 funds tracked by Wall St. Rank held Masimo as of Q1 2026.

Based on Jane Street's 13F filing for Q1 2026, filed 12 May 2026.