Loomis, Sayles & Company
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Loomis, Sayles & Company’s iRhythm Holdings IRTC Stock Holding History

Loomis, Sayles & Company’s Portfolio IRTC Stock Details IRTC Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q1 		$43.4M Sell
367,894
-24,183
-6% -$3.49M 0.06% 117
2025
Q4 		$69.6M Buy
392,077
+102,509
+35% +$18.2M 0.08% 74
2025
Q3 		$49.8M Buy
289,568
+34,051
+13% +$5.41M 0.06% 112
2025
Q2 		$39.3M Buy
+255,517
New +$33M 0.05% 138
2024
Q4 		– Sell
-118,502
Closed -$8.8M – 757
2024
Q3 		$8.8M Sell
118,502
-251,988
-68% -$20.1M 0.01% 375
2024
Q2 		$39.9M Buy
370,490
+64,548
+21% +$6.59M 0.06% 148
2024
Q1 		$35.5M Buy
+305,942
New +$34.4M 0.05% 172
2020
Q4 		– Sell
-244,323
Closed -$58.2M – 814
2020
Q3 		$58.2M Buy
244,323
+47,932
+24% +$8.48M 0.08% 91
2020
Q2 		$22.8M Buy
196,391
+49,219
+33% +$5.43M 0.04% 199
2020
Q1 		$12M Buy
+147,172
New +$12.2M 0.02% 254
2019
Q2 		– Sell
-322,878
Closed -$24.2M – 658
2019
Q1 		$24.2M Sell
322,878
-17,773
-5% -$1.52M 0.05% 172
2018
Q4 		$23.7M Buy
340,651
+6,673
+2% +$506K 0.06% 148
2018
Q3 		$31.6M Sell
333,978
-24,250
-7% -$2.11M 0.06% 152
2018
Q2 		$29.1M Buy
358,228
+2,231
+0.6% +$156K 0.06% 159
2018
Q1 		$22.4M Buy
355,997
+20,509
+6% +$1.27M 0.05% 214
2017
Q4 		$18.8M Buy
+335,488
New +$17.5M 0.04% 280

Other funds holding IRTC

BlackRock
BlackRock New York $5.72T AUM 30.48% 1-Year Est. Return
VPM
Vanguard Portfolio Management Malvern, Pennsylvania $1.91T AUM
RI
RTW Investments New York $10B AUM 135.35% 1-Year Est. Return
Millennium Management
Millennium Management New York $240B AUM 35.51% 1-Year Est. Return
Artisan Partners
Artisan Partners Milwaukee, Wisconsin $62.3B AUM 26.25% 1-Year Est. Return
VCM
Vanguard Capital Management Malvern, Pennsylvania $4.04T AUM
Fidelity Investments
Fidelity Investments Boston, Massachusetts $1.9T AUM 41.92% 1-Year Est. Return
Holocene Advisors
Holocene Advisors New York $41.5B AUM 42.97% 1-Year Est. Return
UBS AM
UBS AM Chicago, Illinois $481B AUM 26.39% 1-Year Est. Return
Geode Capital Management
Geode Capital Management Boston, Massachusetts $1.61T AUM 30.72% 1-Year Est. Return

Loomis, Sayles & Company's IRTC Position: Q1 2026 in Review

Loomis, Sayles & Company reduced its iRhythm Holdings (IRTC) stake by 6.2% in Q1 2026, selling an estimated $3.49M and leaving 367,894 shares worth $43.4M. The position accounts for 0.06% of the portfolio, ranked #117.

Loomis, Sayles & Company first reported a position in IRTC in Q4 2017 and has held it in 16 quarters since. The position peaked at $69.6M in Q4 2025. 304 funds tracked by Wall St. Rank hold IRTC as of Q1 2026.

  • Loomis, Sayles & Company held 367,894 shares of iRhythm Holdings worth $43.4M as of Q1 2026.
  • Loomis, Sayles & Company sold 24,183 iRhythm Holdings shares in Q1 2026, an estimated $3.49M.
  • iRhythm Holdings made up 0.06% of Loomis, Sayles & Company's portfolio in Q1 2026, its #117 holding.
  • Loomis, Sayles & Company first reported a position in iRhythm Holdings in Q4 2017 and has held it in 16 quarters since.
  • Loomis, Sayles & Company's iRhythm Holdings position peaked at $69.6M in Q4 2025.
  • 304 funds tracked by Wall St. Rank held iRhythm Holdings as of Q1 2026.

Based on Loomis, Sayles & Company's 13F filing for Q1 2026, filed 14 May 2026.