Company · Ownership research

RHYTHM PHARMACEUTICALS, INC. RYTM

CIK 0001649904 · CUSIP 76243J105

Insider trading Initial holdings Institutional holders

Quarter-end disclosures, not live holdings.

Several CUSIPs are reported for this company; this page shows CUSIP 76243J105 (RYTM), not CUSIP 76243J955 (RYTM), CUSIP 76243J905 (RYTM), and does not merge CUSIPs.

This page lists the top 20 of 230 rows by value; the complete set is available through the API.

Some filings reported values in thousands; those figures were scaled ×1,000 to dollars.

Top 20 institutions

Weight means this stock's share of the manager's own portfolio.

By reported value

#	Manager	Value	Manager weight	Change vs prior	Source
01	BlackRock, Inc. CIK 2012383 · View history	$363.10M 6,854,755 shares	0.01%	-95.96K(-1.40%)Reduced	SEC filing ↗ May 2, 2025	▾
02	RA CAPITAL MANAGEMENT, L.P. CIK 1346824 · View history	$322.29M 6,084,412 shares	5.38%	0(0.00%)Unchanged	SEC filing ↗ May 15, 2025	▾
03	PRIMECAP MANAGEMENT CO/CA/ CIK 763212 · View history	$306.55M 5,787,322 shares	0.25%	-783.87K(-11.90%)Reduced	SEC filing ↗ May 9, 2025	▾
04	BAKER BROS. ADVISORS LP CIK 1263508 · View history	$296.87M 5,604,483 shares	3.29%	-479.77K(-7.90%)Reduced	SEC filing ↗ May 15, 2025	▾
05	VANGUARD GROUP INC CIK 102909 · View history	$182.48M 3,444,926 shares	0.00%	+2.33K(+0.10%)Added	SEC filing ↗ May 9, 2025	▾
06	NEA Management Company, LLC CIK 1512848 · View history	$154.14M 2,909,956 shares	11.87%	0(0.00%)Unchanged	SEC filing ↗ May 14, 2025	▾
07	PERCEPTIVE ADVISORS LLC CIK 1224962 · Amended · View history	$134.99M 2,548,445 shares	4.79%	-1.13M(-30.80%)Reduced	SEC filing ↗ Aug 6, 2025	▾
08	STATE STREET CORP CIK 93751 · View history	$104.39M 1,970,733 shares	0.00%	+129.86K(+7.10%)Added	SEC filing ↗ May 15, 2025	▾
09	JANUS HENDERSON GROUP PLC CIK 1274173 · View history	$90.75M 1,655,350 shares	0.05%	+435.80K(+35.70%)Added	SEC filing ↗ May 15, 2025	▾
10	FMR LLC CIK 315066 · View history	$89.43M 1,688,375 shares	0.01%	+1.58M(+1,392.70%)Added	SEC filing ↗ May 12, 2025	▾
11	GOLDMAN SACHS GROUP INC CIK 886982 · Amended · View history	$86.76M 1,637,908 shares	0.02%	-174.30K(-9.60%)Reduced	SEC filing ↗ May 16, 2025	▾
12	FEDERATED HERMES, INC. CIK 1056288 · View history	$84.32M 1,591,871 shares	0.18%	+42.24K(+2.70%)Added	SEC filing ↗ May 8, 2025	▾
13	Driehaus Capital Management LLC CIK 938206 · View history	$77.23M 1,458,022 shares	0.74%	+167.05K(+12.90%)Added	SEC filing ↗ May 15, 2025	▾
14	WESTFIELD CAPITAL MANAGEMENT CO LP CIK 1177719 · View history	$71.04M 1,341,092 shares	0.35%	+1.34MNew	SEC filing ↗ May 9, 2025	▾
15	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$68.20M 1,287,168 shares	0.01%	+31.37K(+2.50%)Added	SEC filing ↗ May 13, 2025	▾
16	PRICE T ROWE ASSOCIATES INC /MD/ CIK 80255 · View history	$63.52M 1,199,053 shares	0.01%	+513.90K(+75.00%)Added	SEC filing ↗ May 14, 2025	▾
17	Checkpoint Capital L.P. CIK 1977548 · View history	$48.06M 907,240 shares	26.37%	+179.26K(+24.60%)Added	SEC filing ↗ May 15, 2025	▾
18	Rock Springs Capital Management LP CIK 1595725 · View history	$44.19M 834,188 shares	2.53%	-328.53K(-28.30%)Reduced	SEC filing ↗ May 15, 2025	▾
19	ALKEON CAPITAL MANAGEMENT LLC CIK 1230239 · View history	$43.31M 817,700 shares	0.26%	-350.00K(-30.00%)Reduced	SEC filing ↗ May 15, 2025	▾
20	Frazier Life Sciences Management, L.P. CIK 1892134 · View history	$35.95M 678,760 shares	1.64%	-1.19M(-63.70%)Reduced	SEC filing ↗ May 15, 2025	▾

Showing 20 / 230 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

230

Cancelled or null records excluded

Disclosed shares

64,818,874

Not deduplicated across managers

Disclosed value

$3.44B

Not market cap or free float

Reporting institutions by quarter

Counts also change with data coverage and reporting entities; they do not measure net buying. Distinct managers with a live stock row in this CUSIP; totals may include overlapping filings and are not a share of the company.

RHYTHM PHARMACEUTICALS, INC. · Q1 2025

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Sources, coverage & how to read this data

Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.