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

13F Institutional Holders and Ownership History from Q4 2017 to Q4 2025

Type / Class
Equity / Common Stock, $0.001 par value per share
Symbol
RYTM on Nasdaq
Shares outstanding
67,341,788
Price per share
$105.53
All holders as of 31 Dec 2025
Q4 2025
Total 13F shares
72,859,757
Total reported value
$7,799,438,329
% of total 13F portfolios
0.01%
Share change
+1,939,959
Value change
+$219,309,768
Number of holders
276
Price from insider filings
$105.53
Reported Shares, Excluding Options vs Price
Reported Value, Excluding Options
Total Investors

Significant Owners of RHYTHM PHARMACEUTICALS, INC. - Common Stock, $0.001 par value per share (RYTM) based on Schedule 13D/G filings

Filer Ownership Change % Holdings Value Net Change Nb Shares Change % Reporting Name Report Period
RA CAPITAL MANAGEMENT, L.P. 9.9% +13% $662,816,935 +$109,906,623 6,666,837 +20% RA Capital Management, L.P. 31 Dec 2025
VANGUARD GROUP INC 9.3% +22% $664,816,449 +$129,998,903 6,210,916 +24% The Vanguard Group 31 Dec 2025
BAKER BROS. ADVISORS LP 8.9% $360,984,750 5,604,483 Baker Bros. Advisors LP 31 Mar 2025
PERCEPTIVE ADVISORS LLC 6.8% $284,913,835 4,423,441 Perceptive Advisors LLC 31 Mar 2025
BlackRock, Inc. 6.9% $281,130,327 4,364,700 BlackRock, Inc. 31 Mar 2025
PRIMECAP MANAGEMENT CO/CA/ 5.2% -20% $345,849,272 -$77,964,170 3,478,669 -18% PRIMECAP MANAGEMENT CO/CA/ 31 Dec 2025
GOLDMAN SACHS GROUP INC 3% $117,157,406 1,818,932 THE GOLDMAN SACHS GROUP, INC. 31 Dec 2024

As of 31 Dec 2025, 276 institutional investors reported holding 72,859,757 shares of RHYTHM PHARMACEUTICALS, INC. - Common Stock, $0.001 par value per share (RYTM). This represents 108% of the company’s total 67,341,788 outstanding shares.

Top 25 Institutional Shareholders

The largest institutional shareholders of RHYTHM PHARMACEUTICALS, INC. - Common Stock, $0.001 par value per share (RYTM) together control 83% of the company’s outstanding shares — a level of ownership often associated with strong institutional conviction and long‑term capital commitment.

Institution Ownership % Shares Held Share Change % Portfolio % Holdings Value
RA CAPITAL MANAGEMENT, L.P. 9.9% 6,666,837 +17% 7.3% $713,618,232
BlackRock, Inc. 9.4% 6,297,334 -0.08% 0.01% $674,066,632
VANGUARD GROUP INC 9.2% 6,210,916 +24% 0.01% $664,816,448
BAKER BROS. ADVISORS LP 8.3% 5,604,483 0% 3.5% $599,903,860
PRIMECAP MANAGEMENT CO/CA/ 5.2% 3,478,669 -18% 0.28% $372,356,730
NEA Management Company, LLC 4.3% 2,909,956 0% 16% $311,481,690
PERCEPTIVE ADVISORS LLC 3.8% 2,546,391 +4.4% 5% $272,565,693
STATE STREET CORP 3.3% 2,198,615 +8.4% 0.01% $235,339,750
GOLDMAN SACHS GROUP INC 2.7% 1,830,866 -3.3% 0.03% $195,975,896
FMR LLC 2.5% 1,706,317 -20% 0.01% $182,644,125
FEDERATED HERMES, INC. 2.4% 1,623,841 -6% 0.29% $173,815,940
PRICE T ROWE ASSOCIATES INC /MD/ 2.3% 1,560,847 +11% 0.02% $167,074,000
JPMORGAN CHASE & CO 2.1% 1,423,989 +20% 0.01% $152,423,883
GEODE CAPITAL MANAGEMENT, LLC 2% 1,375,729 +0.95% 0.01% $147,282,636
Driehaus Capital Management LLC 1.9% 1,285,222 -7.1% 0.93% $137,570,163
WESTFIELD CAPITAL MANAGEMENT CO LP 1.9% 1,267,158 +19% 0.57% $135,636,592
Polar Capital Holdings Plc 1.8% 1,185,392 -4.8% 0.58% $126,884,360
JANUS HENDERSON GROUP PLC 1.7% 1,126,125 -3% 0.05% $120,591,241
Checkpoint Capital L.P. 1.5% 992,200 +30% 34% $106,205,088
Capital Research Global Investors 1.5% 985,086 +65% 0.02% $105,443,605
ALLIANCEBERNSTEIN L.P. 1.4% 930,233 -5% 0.03% $99,572,140
JENNISON ASSOCIATES LLC 1.4% 918,567 +123% 0.06% $98,323,416
FRANKLIN RESOURCES INC 1% 695,735 +23% 0.02% $74,471,475
Rock Springs Capital Management LP 1% 695,010 -3.1% 3.8% $74,393,870
Woodline Partners LP 1% 688,779 +19% 0.29% $73,726,904

Institutional Holders of RHYTHM PHARMACEUTICALS, INC. - Common Stock, $0.001 par value per share (RYTM) across Reporting Periods

Period Reported Shares, Excl. Options Value, Excl. Options Value Change Price (Median) Investors
2025 Q4 72,859,757 $7,799,438,329 +$219,309,768 $107.04 276
2025 Q3 70,891,372 $7,159,219,287 +$449,473,544 $100.99 264
2025 Q2 66,543,505 $4,204,958,379 +$136,584,141 $63.19 225
2025 Q1 64,595,384 $3,424,910,613 -$18,829,096 $52.97 226
2024 Q4 64,917,500 $3,634,217,578 -$158,677,402 $55.98 202
2024 Q3 67,700,036 $3,546,202,706 -$85,917,668 $52.39 175
2024 Q2 69,300,680 $2,846,175,742 +$52,795,226 $41.06 164
2024 Q1 68,030,458 $2,946,208,413 +$55,358,404 $43.33 166
2023 Q4 66,696,112 $3,065,811,725 -$41,849,707 $45.97 167
2023 Q3 68,143,293 $1,562,080,292 +$58,456,223 $22.92 143
2023 Q2 66,212,640 $1,092,127,229 +$94,106,398 $16.49 116
2023 Q1 60,335,883 $1,076,382,910 -$49,077,961 $17.84 125
2022 Q4 62,378,764 $1,816,485,551 +$85,568,575 $29.12 116
2022 Q3 59,549,165 $1,446,896,472 +$426,232,319 $24.50 99
2022 Q2 45,934,145 $190,627,988 -$18,795,957 $4.15 82
2022 Q1 48,841,709 $562,605,977 +$4,688,818 $11.52 105
2021 Q4 48,449,400 $483,522,595 -$537,879 $9.98 94
2021 Q3 47,950,622 $626,233,206 +$2,428,146 $13.06 93
2021 Q2 42,614,232 $834,516,313 -$3,429,160 $19.58 101
2021 Q1 47,577,014 $1,011,965,096 +$147,271,703 $21.27 119
2020 Q4 40,510,233 $1,201,291,923 +$39,479,834 $29.73 114
2020 Q3 39,249,591 $850,611,960 -$43,710,727 $21.67 114
2020 Q2 41,237,373 $919,577,883 +$11,957,883 $22.30 89
2020 Q1 40,805,984 $621,064,603 -$34,159,931 $15.22 80
2019 Q4 42,379,694 $973,032,101 +$189,224,828 $22.96 89
2019 Q3 34,304,970 $740,632,813 +$64,825,672 $21.59 84
2019 Q2 31,264,637 $687,757,946 +$9,100,651 $22.00 83
2019 Q1 30,865,613 $846,116,903 -$21,936,591 $27.41 85
2018 Q4 31,656,641 $850,986,460 +$12,828,367 $26.88 73
2018 Q3 31,142,295 $908,421,537 +$2,062,008 $29.17 77
2018 Q2 31,030,594 $970,020,757 +$215,509,581 $31.26 84
2018 Q1 24,362,024 $405,654,613 -$5,856,715 $19.90 54
2017 Q4 21,624,878 $628,421,658 +$507,347,658 $29.06 65