L3VLUP
Quarter end
30 Jun 2025
the date the book describes
Filed
18 Aug 2025
latest of these filings; the earliest 12 Aug 2025
Managers listing it
23
at least, of 95 tracked, among listed positions
Comparable managers
95
filed both Q1 2025 and Q2 2025; 12 listed it in both
Shares listed
37,202,895
combined, among listed positions
Reported value
$3.7bn
combined, at the quarter end

Among the 95 comparable managers: 17 buyers (opened or added shares) and 6 sellers (trimmed or exited), at least, among listed positions. Their net change in shares is not known from listed positions, because at least one of them lists it in only one of the two quarters.

Managers listing INSM in Q2 2025

Share of 13F value is the position’s reported value over everything the manager reported that quarter. The share change is against Q1 2025, and only where both filings list the position. A rise in value with no rise in shares is the price, not buying.

23 of 23 holders

ActionFiling
T. Rowe Price Associates Inc11,230,705$1.1bn0.13%Trimmed-1,692,83614 Aug 2025 (the filing on sec.gov)
Fidelity (FMR LLC)5,093,261$513munder 0.1%Addedn.a.14 Aug 2025 (the filing on sec.gov)
D. E. Shaw & Co.3,422,619$344m0.24%Added+2,687,73914 Aug 2025 (the filing on sec.gov)
Artisan Partners LP3,314,341$334m0.49%Added+97,07312 Aug 2025 (the filing on sec.gov)
Janus Henderson Group Ltd2,293,142$231m0.11%Added+747,72314 Aug 2025 (the filing on sec.gov)
Millennium Management LLC2,121,717$214m0.10%Newnew14 Aug 2025 (the filing on sec.gov)
Holocene Advisors LP2,016,806$203m0.50%Trimmed-9,61614 Aug 2025 (the filing on sec.gov)
Jane Street Group LLC1,352,922$136munder 0.1%Addedn.a.14 Aug 2025 (the filing on sec.gov)
AllianceBernstein LP1,343,212$135munder 0.1%Trimmed-1,080,30114 Aug 2025 (the filing on sec.gov)
Wellington Management Group LLP1,159,699$117munder 0.1%Trimmedn.a.14 Aug 2025 (the filing on sec.gov)
Marshall Wace LLP1,113,361$112m0.13%Added+417,12413 Aug 2025 (the filing on sec.gov)
Maverick Capital Ltd804,133$81m1.22%Added+379,00814 Aug 2025 (the filing on sec.gov)
Point72 Asset Management LP490,667$49m0.10%Newnew14 Aug 2025 (the filing on sec.gov)
Two Sigma Investments LP376,508$38m0.07%Trimmed-30,39514 Aug 2025 (the filing on sec.gov)
Voloridge Investment Management LLC313,053$32m0.12%Addedn.a.14 Aug 2025 (the filing on sec.gov)
Woodline Partners LP248,921$25m0.13%Added+15114 Aug 2025 (the filing on sec.gov)
Brevan Howard Capital Management LP202,594$20m0.12%Newnew14 Aug 2025 (the filing on sec.gov)
ExodusPoint Capital Management LP92,717$9.3m0.08%Added+4,93413 Aug 2025 (the filing on sec.gov)
Schonfeld Strategic Advisors LLC83,439$8.4m0.06%Addedn.a.14 Aug 2025 (the filing on sec.gov)
Hudson Bay Capital Management LP81,743$8.2munder 0.1%Addedn.a.18 Aug 2025 (the filing on sec.gov)
Winton Group Ltd22,268$2.2m0.11%Newnew14 Aug 2025 (the filing on sec.gov)
Quantbot Technologies LP22,067$2.2m0.06%Newnew13 Aug 2025 (the filing on sec.gov)
Farallon Capital Management LLC3,000$302kunder 0.1%Held014 Aug 2025 (the filing on sec.gov)

Largest increases and reductions, by shares

Q1 2025 to Q2 2025, among managers that listed it in both quarters or opened it.

Increases

Reductions

New positions and exits

At least these many: a manager is shown exiting only where its own filing shows the position gone.

Ownership over time

Every quarter on file. A quarter-end value moves with the price as well as with the shares held; buyers and sellers count comparable managers, by shares.
18 in Q3 2024 to 21 in Q2 2026

Tracked managers listing it, at least.

0102030201420182020202220242026
the quarter shown share split complete books; unmarked quarters rest on listed positionsClick a quarter to open it.
INSM by quarter
QuarterHoldersReported valueBuyersSellers
Q3 20131$20mn.a.n.a.
Q4 20131$28mn.a.n.a.
Q1 20142$39mn.a.n.a.
Q2 20142$43mn.a.n.a.
Q3 20141$34mn.a.n.a.
Q4 20141$44mn.a.n.a.
Q1 20151$174mn.a.n.a.
Q2 20151$211mn.a.n.a.
Q3 20151$168mn.a.n.a.
Q4 20152$169mn.a.n.a.
Q3 20161$146mn.a.n.a.
Q1 20171$189mn.a.n.a.
Q2 20174$180mn.a.n.a.
Q3 20177$890mn.a.n.a.
Q4 20174$954mn.a.n.a.
Q1 20183$428mn.a.n.a.
Q2 20183$475mn.a.n.a.
Q3 20184$416mn.a.n.a.
Q4 20181$150mn.a.n.a.
Q1 20194$897mn.a.n.a.
Q2 20196$559mn.a.n.a.
Q3 20196$284mn.a.n.a.
Q4 20196$680mn.a.n.a.
Q1 20207$472mn.a.n.a.
Q2 20207$1.0bnn.a.n.a.
Q3 20209$1.2bnn.a.n.a.
Q4 20208$1.0bnn.a.n.a.
Q1 20216$816mn.a.n.a.
Q2 20216$800mn.a.n.a.
Q3 20217$803mn.a.n.a.
Q4 20217$760mn.a.n.a.
Q1 20228$680mn.a.n.a.
Q2 20227$566mn.a.n.a.
Q3 202210$379mn.a.n.a.
Q4 20228$360mn.a.n.a.
Q1 20236$282mn.a.n.a.
Q2 20236$353mn.a.n.a.
Q3 20237$415mn.a.n.a.
Q4 20238$539m45
Q1 20248$437m73
Q2 202416$2.2bn106
Q3 202418$2.3bn1010
Q4 202414$1.6bn48
Q1 202514$1.9bn94
Q2 202523$3.7bn176
Q3 202520$5.8bn109
Q4 202519$6.6bn1420
Q1 202619$7.0bn1617
Q2 202621$5.0bn2811

Compare with…

Holders over time, buyers and sellers, and the managers holding both, side by side for up to four stocks.

INSM and LLY →INSM and JNJ →INSM and VRTX →Choose a stock to compare with INSM →

How much of the picture this is

A 13F is a manager’s long US-listed equity book at a quarter end, filed up to 45 days later. It shows no shorts, cash, bonds or performance, and it is never today’s portfolio. Large books are listed to their largest positions, so a manager missing from this table may still hold a small position below that line. These are 95 tracked managers, not the institutional market.

Which funds own INSM, latest filings →Back to the 13F Explorer →