GAMCO Investors’s Masimo MASI Stock Holding History

GAMCO Investors’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	$16.4M	Buy	92,000 +9,000	+11%	+$1.41M	0.16%	179
2025 Q4	$10.8M	Sell	83,000 -800	-1%	-$115K	0.1%	222
2025 Q3	$12.4M	Sell	83,800 -700	-0.8%	-$106K	0.12%	209
2025 Q2	$14.2M	Hold	84,500	–	–	0.14%	179
2025 Q1	$14.1M	Hold	84,500	–	–	0.16%	169
2024 Q4	$14M	Hold	84,500	–	–	0.15%	179
2024 Q3	$11.3M	Hold	84,500	–	–	0.12%	212
2024 Q2	$10.6M	Hold	84,500	–	–	0.12%	211
2024 Q1	$12.4M	Hold	84,500	–	–	0.13%	197
2023 Q4	$9.9M	Hold	84,500	–	–	0.11%	223
2023 Q3	$7.41M	Hold	84,500	–	–	0.09%	254
2023 Q2	$13.9M	Sell	84,500 -500	-0.6%	-$87K	0.15%	180
2023 Q1	$15.7M	Hold	85,000	–	–	0.17%	161
2022 Q4	$12.6M	Hold	85,000	–	–	0.14%	186
2022 Q3	$12M	Hold	85,000	–	–	0.14%	186
2022 Q2	$11.1M	Hold	85,000	–	–	0.12%	214
2022 Q1	$12.4M	Sell	85,000 -2,500	-3%	-$480K	0.11%	217
2021 Q4	$25.6M	Sell	87,500 -1,000	-1%	-$285K	0.22%	132
2021 Q3	$24M	Sell	88,500 -1,000	-1%	-$271K	0.21%	136
2021 Q2	$21.7M	Sell	89,500 -500	-0.6%	-$114K	0.18%	154
2021 Q1	$20.7M	Sell	90,000 -2,000	-2%	-$502K	0.18%	154
2020 Q4	$24.7M	Sell	92,000 -2,000	-2%	-$499K	0.23%	129
2020 Q3	$22.2M	Sell	94,000 -1,000	-1%	-$224K	0.25%	122
2020 Q2	$21.7M	Sell	95,000 -4,000	-4%	-$878K	0.25%	119
2020 Q1	$17.5M	Sell	99,000 -3,000	-3%	-$515K	0.21%	141
2019 Q4	$16.1M	Sell	102,000 -1,500	-1%	-$225K	0.13%	193
2019 Q3	$15.4M	Sell	103,500 -4,500	-4%	-$684K	0.13%	191
2019 Q2	$16.1M	Hold	108,000	–	–	0.12%	202
2019 Q1	$14.9M	Sell	108,000 -1,000	-0.9%	-$126K	0.11%	208
2018 Q4	$11.7M	Sell	109,000 -3,000	-3%	-$335K	0.1%	217
2018 Q3	$13.9M	Sell	112,000 -6,000	-5%	-$666K	0.09%	229
2018 Q2	$11.5M	Sell	118,000 -4,000	-3%	-$380K	0.08%	243
2018 Q1	$10.7M	Sell	122,000 -500	-0.4%	-$43.6K	0.07%	252
2017 Q4	$10.4M	Sell	122,500 -2,500	-2%	-$217K	0.07%	256
2017 Q3	$10.8M	Sell	125,000 -5,000	-4%	-$442K	0.07%	254
2017 Q2	$11.9M	Hold	130,000	–	–	0.08%	247
2017 Q1	$12.1M	Hold	130,000	–	–	0.08%	236
2016 Q4	$8.76M	Sell	130,000 -200	-0.2%	-$12.3K	0.06%	274
2016 Q3	$7.75M	Hold	130,200	–	–	0.05%	290
2016 Q2	$6.84M	Sell	130,200 -1,200	-0.9%	-$56.5K	0.05%	316
2016 Q1	$5.5M	Sell	131,400 -600	-0.5%	-$22.6K	0.04%	352
2015 Q4	$5.48M	Sell	132,000 -2,000	-1%	-$81.7K	0.04%	354
2015 Q3	$5.17M	Hold	134,000	–	–	0.03%	372
2015 Q2	$5.19M	Hold	134,000	–	–	0.03%	390
2015 Q1	$4.42M	Hold	134,000	–	–	0.02%	415
2014 Q4	$3.53M	Buy	134,000 +9,000	+7%	+$222K	0.02%	449
2014 Q3	$2.66M	Buy	125,000 +3,000	+2%	+$68.5K	0.01%	502
2014 Q2	$2.88M	Buy	122,000 +32,000	+36%	+$794K	0.02%	489
2014 Q1	$2.46M	Buy	90,000 +56,000	+165%	+$1.6M	0.01%	492
2013 Q4	$994K	Buy	+34,000	New	+$952K	0.01%	614

Other funds holding MASI

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 London, United Kingdom $416B AUM 33.63% 1-Year Est. Return

HBK Investments Dallas, Texas $9.85B AUM 55.6% 1-Year Est. Return

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 Boston, Massachusetts $1.9T AUM 41.92% 1-Year Est. Return

State Street Boston, Massachusetts $2.9T AUM 29.55% 1-Year Est. Return

GAMCO Investors's MASI Position: Q1 2026 in Review

GAMCO Investors increased its Masimo (MASI) stake by 11% in Q1 2026, buying an estimated $1.41M and bringing the position to 92,000 shares worth $16.4M. The position accounts for 0.16% of the portfolio, ranked #179.

GAMCO Investors first reported a position in MASI in Q4 2013 and has held it in 50 quarters since. The position peaked at $25.6M in Q4 2021. 445 funds tracked by Wall St. Rank hold MASI as of Q1 2026.

GAMCO Investors held 92,000 shares of Masimo worth $16.4M as of Q1 2026.
GAMCO Investors bought 9,000 Masimo shares in Q1 2026, an estimated $1.41M.
Masimo made up 0.16% of GAMCO Investors's portfolio in Q1 2026, its #179 holding.
GAMCO Investors first reported a position in Masimo in Q4 2013 and has held it in 50 quarters since.
GAMCO Investors's Masimo position peaked at $25.6M in Q4 2021.
445 funds tracked by Wall St. Rank held Masimo as of Q1 2026.

Based on GAMCO Investors's 13F filing for Q1 2026, filed 14 May 2026.