Rhythm Pharmaceuticals, Inc.
MX ˙ BMV ˙ US76243J1051
SecurityMX:RYTM / Rhythm Pharmaceuticals, Inc.
InstitutionGeode Capital Management, Llc
Latest Disclosed Ownership1,416,269 shares
Latest Disclosed Value $ 123,197,314
Geode Capital Management, Llc reports 2.95% increase in ownership of RYTM / Rhythm Pharmaceuticals, Inc.

On May 15, 2026 - Geode Capital Management, Llc filed a 13F-HR form disclosing ownership of 1,416,269 shares of Rhythm Pharmaceuticals, Inc. (MX:RYTM) valued at $123,197,314 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 9, 2026 disclosing 1,375,729 shares of Rhythm Pharmaceuticals, Inc.. This represents a change in shares of 2.95% during the quarter.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-05-15 2026-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 1,416,269 40,540 2.95 123,197 -16.35 0.0041
2026-02-09 2025-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 1,375,729 12,900 0.95 147,283 6.99 0.0091
2025-11-12 2025-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 1,362,829 51,576 3.93 137,654 66.11 0.0088
2025-08-08 2025-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 1,311,253 24,085 1.87 82,868 21.51 0.0058
2025-05-13 2025-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 1,287,168 31,369 2.50 68,197 -3.01 0.0054
2025-02-12 2024-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 1,255,799 -389 -0.03 70,316 6.82 0.0054
2024-11-12 2024-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 1,256,188 3,499 0.28 65,824 27.95 0.0053
2024-08-09 2024-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 1,252,689 71,984 6.10 51,445 0.54 0.0045
2024-05-13 2024-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 1,180,705 61,576 5.50 51,167 -0.55 0.0047
2024-02-13 2023-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 1,119,129 74,072 7.09 51,452 114.74 0.0054
2023-11-13 2023-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 1,045,057 71,707 7.37 23,961 49.28 0.0029
2023-08-11 2023-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 973,350 500,589 105.89 16,051 90.30 0.0019
2023-05-15 2023-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 472,761 14,251 3.11 8,434 64,776.92 0.0011
2023-02-13 2022-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 458,510 70,398 18.14 13 -99.86 0.0019
2022-11-14 2022-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 388,112 -11,682 -2.92 9,508 473.12 0.0014
2022-08-12 2022-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 399,794 -341,095 -46.04 1,659 -80.56 0.0002
2022-05-13 2022-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 740,889 26,861 3.76 8,535 19.79 0.0011
2022-02-11 2021-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 714,028 46,370 6.95 7,125 -18.28 0.0009
2021-11-12 2021-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 667,658 -17,245 -2.52 8,719 -34.98 0.0012
2021-08-13 2021-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 684,903 61,341 9.84 13,410 1.11 0.0018
2021-05-12 2021-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 623,562 135,115 27.66 13,263 -8.66 0.0020
2021-02-12 2020-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 488,447 -3,232 -0.66 14,521 36.30 0.0024
2020-11-13 2020-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 491,679 14,929 3.13 10,654 0.22 0.0021
2020-08-13 2020-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 476,750 33,493 7.56 10,631 57.59 0.0023
2020-05-14 2020-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 443,257 45,382 11.41 6,746 -26.15 0.0018
2020-02-20 2019-12-31 13F/A-1 RHYTHM PHARMACEUTICALS COM 76243J105 397,875 80,602 25.40 9,135 33.38 0.0019
2020-02-13 2019-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 397,875 80,602 9,135 1,164.1757
2019-11-12 2019-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 317,273 4,737 1.52 6,849 -0.38 0.0016
2019-08-14 2019-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 312,536 60,519 24.01 6,875 -0.46 0.0017
2019-05-14 2019-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 252,017 18,123 7.75 6,907 9.86 0.0018
2019-03-06 2018-12-31 13F/A-1 RHYTHM PHARMACEUTICALS COM 76243J105 233,894 54,247 30.20 6,287 19.98 0.0019
2019-02-13 2018-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 233,894 54,247 6,287
2018-11-13 2018-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 179,647 88,819 97.79 5,240 84.57 0.0015
2018-08-14 2018-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 90,828 -28,530 -23.90 2,839 19.54 0.0009
2018-05-15 2018-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 119,358 -4,437 -3.58 2,375 -33.97 0.0008
2018-02-13 2017-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 123,795 123,795 3,597 0.0012
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.