L3VLUP
ProSign in

RYTM in the 13F filings

Rhythm Pharmaceuticals Inc · CUSIP 76243J105

Sector · Pharmaceuticals and biotechnologyTheme · Healthcare: biopharma and medtech· L3VLUP-definedTheme · Pharmaceutical preparations
Quarter
Q3 2026 · early filersQ2 2026Q1 2026Q4 2025Q3 2025Q2 2025Q1 2025Q4 2024Q3 2024Q2 2024Q1 2024Q4 2023
Quarter end
31 Dec 2025
the date the book describes
Filed
27 Oct 2026
latest of these filings; the earliest 10 Feb 2026
Managers listing it
28
at least, of 95 tracked, among listed positions
Comparable managers
92
filed both Q3 2025 and Q4 2025; 9 listed it in both
Shares listed
9,532,982
combined, among listed positions
Reported value
$1.0bn
combined, at the quarter end

Among the 92 comparable managers: 16 buyers (opened or added shares) and 16 sellers (trimmed or exited), at least, among listed positions. Their net change in shares was +106,756.

Managers listing RYTM in Q4 2025

Share of 13F value is the position’s reported value over everything the manager reported that quarter. The share change is against Q3 2025, and only where both filings list the position. A rise in value with no rise in shares is the price, not buying.

28 of 28 holders

ActionFiling
Fidelity (FMR LLC)1,706,317$183munder 0.1%Trimmed-438,86617 Feb 2026 (the filing on sec.gov)
T. Rowe Price Associates Inc1,560,847$167munder 0.1%Added+160,95017 Feb 2026 (the filing on sec.gov)
Janus Henderson Group Ltd1,126,125$121m0.05%Trimmed-34,76217 Feb 2026 (the filing on sec.gov)
Capital Research Global Investors985,086$105munder 0.1%Added+386,83911 Feb 2026 (the filing on sec.gov)
AllianceBernstein LP930,233$100munder 0.1%Trimmed-49,44917 Feb 2026 (the filing on sec.gov)
Woodline Partners LP688,779$74m0.29%Added+108,59617 Feb 2026 (the filing on sec.gov)
Point72 Asset Management LP429,420$46m0.05%Newnew17 Feb 2026 (the filing on sec.gov)
Renaissance Technologies LLC341,193$37m0.06%Trimmed-205,40012 Feb 2026 (the filing on sec.gov)
Invesco Ltd291,150$31munder 0.1%Added+147,59519 Feb 2026 (the filing on sec.gov)
Artisan Partners LP263,591$28munder 0.1%Added+26,75017 Feb 2026 (the filing on sec.gov)
Wellington Management Group LLP250,156$27munder 0.1%Added+225,67917 Feb 2026 (the filing on sec.gov)
Millennium Management LLC186,709$20munder 0.1%Added+53,54817 Feb 2026 (the filing on sec.gov)
Citadel Advisors LLC153,322$16munder 0.1%Added+20,69617 Feb 2026 (the filing on sec.gov)
Capital World Investors115,693$12munder 0.1%Newnew11 Feb 2026 (the filing on sec.gov)
ExodusPoint Capital Management LP75,141$8.0m0.06%Newnew17 Feb 2026 (the filing on sec.gov)
Neuberger Berman Group LLC73,572$7.9munder 0.1%Trimmed-11,54527 Oct 2026 (the filing on sec.gov)
Balyasny Asset Management LLC72,282$7.7munder 0.1%Trimmed-277,72617 Feb 2026 (the filing on sec.gov)
AQR Capital Management LLC70,046$7.5munder 0.1%Trimmed-9,73417 Feb 2026 (the filing on sec.gov)
Voloridge Investment Management LLC60,575$6.5munder 0.1%Trimmed-307,68817 Feb 2026 (the filing on sec.gov)
PDT Partners LLC59,436$6.4m0.41%Trimmed-26,70017 Feb 2026 (the filing on sec.gov)
Squarepoint Ops LLC32,829$3.5munder 0.1%Newnew13 Feb 2026 (the filing on sec.gov)
D. E. Shaw & Co.31,356$3.4munder 0.1%Added+27,77117 Feb 2026 (the filing on sec.gov)
Man Group PLC9,558$1.0munder 0.1%Trimmed-119,77217 Feb 2026 (the filing on sec.gov)
Acadian Asset Management LLC6,105$652kunder 0.1%Newnew10 Feb 2026 (the filing on sec.gov)
Verition Fund Management LLC4,504$482kunder 0.1%Newnew13 Feb 2026 (the filing on sec.gov)
Page 1 of 2

Largest increases and reductions, by shares

Q3 2025 to Q4 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.

New (6)

Exited (4)

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.
6 in Q3 2024 to 9 in Q2 2026

Tracked managers listing it, at least.

03581020182019202020212022202420252026
the quarter shown share split complete books; unmarked quarters rest on listed positionsClick a quarter to open it.
RYTM by quarter
QuarterHoldersReported valueBuyersSellers
Q1 20181$750kn.a.n.a.
Q2 20183$76mn.a.n.a.
Q3 20183$91mn.a.n.a.
Q4 20181$88mn.a.n.a.
Q1 20192$90mn.a.n.a.
Q2 20191$72mn.a.n.a.
Q3 20191$74mn.a.n.a.
Q4 20191$99mn.a.n.a.
Q1 20201$66mn.a.n.a.
Q2 20201$98mn.a.n.a.
Q3 20201$95mn.a.n.a.
Q4 20201$134mn.a.n.a.
Q1 20211$87mn.a.n.a.
Q2 20211$77mn.a.n.a.
Q4 20211$593kn.a.n.a.
Q1 20221$474kn.a.n.a.
Q2 20221$628kn.a.n.a.
Q3 20222$43mn.a.n.a.
Q4 20221$36mn.a.n.a.
Q3 20233$33mn.a.n.a.
Q4 20234$61m31
Q1 20243$40m20
Q2 20244$32m13
Q3 20246$80m43
Q4 20244$131m41
Q1 20254$147m31
Q2 20255$160m23
Q3 20259$496m72
Q4 202510$537m1616
Q1 20267$450m1814
Q2 20269$859m1418

Compare with…

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

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

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 RYTM, latest filings →Back to the 13F Explorer →