리듬 파마슈티컬스, Inc.
MX ˙ BMV ˙ US76243J1051
SecurityMX:RYTM / Rhythm Pharmaceuticals, Inc.
InstitutionAmeriprise Financial Inc
Latest Disclosed Ownership383,957 shares
Latest Disclosed Value $ 33,392,899
Ameriprise Financial Inc reports 47.02% increase in ownership of RYTM / Rhythm Pharmaceuticals, Inc.

On May 15, 2026 - Ameriprise Financial Inc filed a 13F-HR form disclosing ownership of 383,957 shares of Rhythm Pharmaceuticals, Inc. (MX:RYTM) valued at $33,392,899 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 261,160 shares of Rhythm Pharmaceuticals, Inc.. This represents a change in shares of 47.02% 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 383,957 122,797 47.02 33,393 19.45 0.0014
2026-02-17 2025-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 261,160 123,193 89.29 27,955 100.63 0.0063
2025-11-14 2025-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 137,967 -35,102 -20.28 13,933 27.40 0.0032
2025-08-14 2025-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 173,069 74,788 76.10 10,936 110.11 0.0027
2025-05-14 2025-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 98,281 44,914 84.16 5,206 74.26 0.0014
2025-02-14 2024-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 53,367 11,480 27.41 2,987 36.14 0.0008
2024-11-14 2024-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 41,887 1,472 3.64 2,194 32.25 0.0006
2024-08-14 2024-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 40,415 19,435 92.64 1,659 82.51 0.0004
2024-05-15 2024-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 20,980 0 0.00 909 -5.71 0.0003
2024-02-14 2023-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 20,980 -1,000 -4.55 964 91.65 0.0003
2023-11-14 2023-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 21,980 3,840 21.17 504 68.23 0.0002
2023-08-14 2023-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 18,140 0 0.00 299 -7.43 0.0001
2023-05-22 2023-03-31 13F/A-1 RHYTHM PHARMACEUTICALS COM 76243J105 18,140 0 0.00 324 -38.83 0.0001
2023-05-15 2023-03-31 13F REYNOLDS CONSUMER PRODUCTS I COM 76243J105 18,140 0 324 0.0000
2023-02-14 2022-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 18,140 0 0.00 528 18.65 0.0002
2022-11-14 2022-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 18,140 0 0.00 445 493.33 0.0002
2022-08-15 2022-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 18,140 18,140 75 0.0000
2021-05-17 2021-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 0 -8,410 -100.00 0 -100.00
2021-02-12 2020-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 8,410 8,410 250 0.0001
2020-05-15 2020-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 0 -12,610 -100.00 0 -100.00
2020-02-14 2019-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 12,610 -25,000 -66.47 290 -64.29 0.0001
2019-11-14 2019-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 37,610 37,610 812 0.0004
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.