RHYTHM PHARMACEUTICALS, INC. - Common Stock, $0.001 par value per share (RYTM)

Q: What does CUSIP 76243J105 represent in this 13F holders report?

CUSIP 76243J105 is the security identifier for RYTM - RHYTHM PHARMACEUTICALS, INC. - Common Stock, $0.001 par value per share used to aggregate holder disclosures.

Q: How many institutions held RYTM - RHYTHM PHARMACEUTICALS, INC. - Common Stock, $0.001 par value per share in Q4 2025?

279 institutional investors reported RYTM - RHYTHM PHARMACEUTICALS, INC. - Common Stock, $0.001 par value per share for Q4 2025. Use the holders table for investor-level position and value details.

CUSIP: 76243J105

Q4 2025 13F Holders as of 31 Dec 2025

Security type / class: Equity / Common Stock, $0.001 par value per share
Total 13F shares: 72,869,773
Total 13F value: $7,800,510,442
Share change: +1,953,240
Put/Call ratio: 73%
SEC-reported price per share: $107.04
Number of holders: 279
Value change: +$220,704,819
Number of buys: 155
Number of sells: 128
Shares outstanding: 69,012,275

Security key

76243J105

Report period

Q4 2025

Institutions

279

Top holders

RYTM full security history Ownership snapshot Full 13F holder table Newer quarter: Q1 2026 Previous quarter: Q3 2025 RHYTHM PHARMACEUTICALS, INC. SEC filings RHYTHM PHARMACEUTICALS, INC. company facts

Broader feeds

Latest 13F filings Latest 13D/G filings Investors directory

Reporting periods

Holder history for CUSIP 76243J105

Newer quarter: Q1 2026 Previous quarter: Q3 2025

Recent filing periods:

Q2 2026 Q1 2026 Q4 2025 Q3 2025 Q2 2025 Q1 2025 Q4 2024 Q3 2024

Ownership snapshot

Top reported holders of RYTM - RHYTHM PHARMACEUTICALS, INC. - Common Stock, $0.001 par value per share (13F + 13D/G + 3/4/5)

Grouped by holder across the latest SEC ownership disclosures. Start with comparable ownership when available, then verify the linked 13F, 13D/G, or 3/4/5 evidence.

Comparable stake leader

RA CAPITAL MANAGEMENT, L.P.

Disclosed value leader

RA CAPITAL MANAGEMENT, L.P.

Comparable rows

15/15

Latest evidence

31 Dec 2025

13D/G 13F Lead comparable stake: 9.9% 13D/G row: RA CAPITAL MANAGEMENT, L.P. Showing 1-6 of 15 holder rows.

Quick read

RA CAPITAL MANAGEMENT, L.P. leads the comparable SEC ownership view at 9.9%.

15 of 15 rows have a safely comparable ownership percentage. Use this as a filing-backed starting point, then open the detailed table for source links, reporting role, position value, share count, and filing date.

Open SEC evidence Opens RA CAPITAL MANAGEMENT, L.P.'s linked filing trail.

Comparable ownership Top 5

RA CAPITAL MANAGEMENT, L.P. 9.9%

BAKER BROS. ADVISORS LP 8.9%

BlackRock, Inc. 6.9%

PRIMECAP MANAGEMENT CO/CA/ 5.2%

GOLDMAN SACHS GROUP INC 3%

Ownership % is shown only when SEC disclosures are safely comparable across share classes.

Detailed SEC evidence table Showing 1-6 of 15 holder rows

Holder	Evidence	Ownership %	Position	12M Net Δ	As of
RA CAPITAL MANAGEMENT, L.P.	13D/G 13F Company 13D/G 13F	9.9%	$662,816,935 6,666,837 shares	+$109,906,623	31 Dec 2025
BAKER BROS. ADVISORS LP	13F 13D/G Company 13F 13D/G	8.9% from 13D/G	$565,996,738 5,604,483 shares	—	30 Sep 2025
BlackRock, Inc.	13F 13D/G Company 13F 13D/G	6.9% from 13D/G	$636,460,694 6,302,215 shares	—	30 Sep 2025
PRIMECAP MANAGEMENT CO/CA/	13F 13D/G Company 13F 13D/G	5.2% from 13D/G	$430,506,130 4,262,859 shares	—	30 Sep 2025
GOLDMAN SACHS GROUP INC	13F 13D/G Company · THE GOLDMAN SACHS GROUP, INC. 13F 13D/G	3% from 13D/G	$191,241,026 1,893,663 shares	—	30 Sep 2025
VANGUARD GROUP INC	13F Company 13F	7.2%	$504,589,163 4,996,427 shares	—	30 Sep 2025

How to read this table

Rows are grouped by holder and ranked first by SEC-reported ownership % when it is safely comparable, then by disclosed holdings value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.

13F holder rows

Institutional holders as of Q4 2025

Investor-level positions for this CUSIP, loaded as an interactive table.

Institutions

279

72,869,773

Rows available

279

Investor	Option	Weight %	Change %	SEC-reported value	* Price	Shares	Share Change	Activity	Report Period

^* SEC-reported price is the security price as of the portfolio date and can indicate the last known price at which the security was still held. The marker flags a reported price that did not pass the local price check.

Compare Q4 2025 vs Q3 2025 Across Filers

Q3 2025 holders

263

Q4 2025 holders

279

Holder diff

Investor	Q3 2025 Shares	Q4 2025 Shares	Share Diff	Share Chg %	Q3 2025 value	Q4 2025 value	Value change	Value Chg %

Trend: ostatnie 8 kwartałów (+ wybrane okresy porównania).

Quarterly Holders Trend

Quarterly Value Trend

Quarterly Shares Trend