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WESTFIELD CAPITAL MANAGEMENT CO LP

Position in INSM — INSMED Inc

CIK 1177719 BOSTON, MA

Position in INSM

as of Mar 31, 2026 · filed May 11, 2026
Position Value
$240,122,415
+$164,846,461 QoQ
Shares Held
1,468,459
+239.5% QoQ
Ownership
0.677%
of shares outstanding
% of Portfolio
1.01%
of 13F equity value
Holder Rank
not a current holder
Holding Since
Jun 2020
12 quarters on record
Voting authority Sole 86.028142426857.ToString("F0")% Shared 0.ToString("F0")% None 13.971857573143001.ToString("F0")%

Common Shares in INSM Over Time

Shares Held

Position Value (USD)

Position in Biotechnology

Healthcare · as of Mar 31, 2026

WESTFIELD CAPITAL MANAGEMENT CO LP holds $2,468,245,086 across 19 Biotechnology names. INSM ranks #2 (9.7% of the industry book) .

# Ticker Company Shares Value (USD) Open
2 INSM
INSMED Inc
This page
1,468,459 $240,122,415

All Filings in INSM

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12 filing rows on record
Report Date Value (USD) Shares
2026-03-31 $240,122,415 1,468,459
2025-12-31 $75,275,954 432,521
2025-09-30 $70,266,367 487,927
2025-06-30 $134,785,944 1,339,288
2025-03-31 $107,310,200 1,406,609
2024-12-31 $64,797,561 938,551
2024-09-30 $18,376,947 251,739
2021-06-30 $27,523,068 967,079
2021-03-31 $34,850,600 1,023,212
2020-12-31 $42,567,124 1,278,676
2020-09-30 $42,826,164 1,332,488
2020-06-30 $28,551,020 1,036,711