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 229 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	$396.05M 6,267,538 shares	0.01%	-587.22K(-8.60%)Reduced	SEC filing ↗ Aug 12, 2025	▾
02	BAKER BROS. ADVISORS LP CIK 1263508 · View history	$354.15M 5,604,483 shares	3.44%	0(0.00%)Unchanged	SEC filing ↗ Aug 14, 2025	▾
03	RA CAPITAL MANAGEMENT, L.P. CIK 1346824 · View history	$351.42M 5,561,359 shares	5.92%	-523.05K(-8.60%)Reduced	SEC filing ↗ Aug 14, 2025	▾
04	PRIMECAP MANAGEMENT CO/CA/ CIK 763212 · View history	$308.24M 4,878,037 shares	0.24%	-909.28K(-15.70%)Reduced	SEC filing ↗ Aug 11, 2025	▾
05	VANGUARD GROUP INC CIK 102909 · View history	$226.80M 3,589,114 shares	0.00%	+144.19K(+4.20%)Added	SEC filing ↗ Aug 11, 2025	▾
06	NEA Management Company, LLC CIK 1512848 · View history	$183.88M 2,909,956 shares	13.84%	0(0.00%)Unchanged	SEC filing ↗ Aug 14, 2025	▾
07	PERCEPTIVE ADVISORS LLC CIK 1224962 · View history	$152.81M 2,418,299 shares	5.73%	-130.15K(-5.10%)Reduced	SEC filing ↗ Aug 14, 2025	▾
08	FMR LLC CIK 315066 · View history	$123.44M 1,953,441 shares	0.01%	+265.07K(+15.70%)Added	SEC filing ↗ Aug 14, 2025	▾
09	STATE STREET CORP CIK 93751 · View history	$120.54M 1,907,601 shares	0.00%	-63.13K(-3.20%)Reduced	SEC filing ↗ Aug 14, 2025	▾
10	GOLDMAN SACHS GROUP INC CIK 886982 · View history	$109.55M 1,733,722 shares	0.02%	+95.81K(+5.80%)Added	SEC filing ↗ Aug 14, 2025	▾
11	FEDERATED HERMES, INC. CIK 1056288 · View history	$106.57M 1,686,494 shares	0.20%	+94.62K(+5.90%)Added	SEC filing ↗ Aug 13, 2025	▾
12	WESTFIELD CAPITAL MANAGEMENT CO LP CIK 1177719 · View history	$102.97M 1,629,468 shares	0.43%	+288.38K(+21.50%)Added	SEC filing ↗ Aug 12, 2025	▾
13	JANUS HENDERSON GROUP PLC CIK 1274173 · View history	$89.27M 1,411,902 shares	0.04%	-243.45K(-14.70%)Reduced	SEC filing ↗ Aug 14, 2025	▾
14	PRICE T ROWE ASSOCIATES INC /MD/ CIK 80255 · View history	$84.76M 1,341,392 shares	0.01%	+142.34K(+11.90%)Added	SEC filing ↗ Aug 14, 2025	▾
15	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$82.87M 1,311,253 shares	0.01%	+24.09K(+1.90%)Added	SEC filing ↗ Aug 8, 2025	▾
16	Driehaus Capital Management LLC CIK 938206 · View history	$80.25M 1,269,952 shares	0.64%	-188.07K(-12.90%)Reduced	SEC filing ↗ Aug 14, 2025	▾
17	Polar Capital Holdings Plc CIK 1837309 · View history	$79.04M 1,250,870 shares	0.41%	+750.87K(+150.20%)Added	SEC filing ↗ Aug 14, 2025	▾
18	Checkpoint Capital L.P. CIK 1977548 · View history	$66.98M 1,060,000 shares	31.21%	+152.76K(+16.80%)Added	SEC filing ↗ Aug 14, 2025	▾
19	ALKEON CAPITAL MANAGEMENT LLC CIK 1230239 · View history	$64.31M 1,017,700 shares	0.31%	+200.00K(+24.50%)Added	SEC filing ↗ Aug 14, 2025	▾
20	Rock Springs Capital Management LP CIK 1595725 · View history	$54.42M 861,153 shares	3.39%	+26.96K(+3.20%)Added	SEC filing ↗ Aug 14, 2025	▾

Showing 20 / 229 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

229

Cancelled or null records excluded

Disclosed shares

66,539,256

Not deduplicated across managers

Disclosed value

$4.20B

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. · Q2 2025

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This page includes 20 of 229 reporting institutions. Log in to look up the full history beyond 3 years, use advanced screening & filtering, download CSV, and get the complete set through the Akkru API.

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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.