Rhythm Pharmaceuticals, Inc.
MX ˙ BMV ˙ US76243J1051
SecurityMX:RYTM / Rhythm Pharmaceuticals, Inc.
InstitutionRhumbline Advisers
Latest Disclosed Ownership69,858 shares
Latest Disclosed Value $ 6,075,534
Rhumbline Advisers reports 1.90% decrease in ownership of RYTM / Rhythm Pharmaceuticals, Inc.

On May 12, 2026 - Rhumbline Advisers filed a 13F-HR form disclosing ownership of 69,858 shares of Rhythm Pharmaceuticals, Inc. (MX:RYTM) valued at $6,075,534 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 71,212 shares of Rhythm Pharmaceuticals, Inc.. This represents a change in shares of -1.90% 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)
2026-05-12 2026-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 69,858 -1,354 -1.90 6,076 -20.30 0.0052
2026-02-13 2025-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 71,212 -10,856 -13.23 7,623 -8.04 0.0062
2025-11-06 2025-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 82,068 -5,458 -6.24 8,288 49.87 0.0067
2025-08-12 2025-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 87,526 1,807 2.11 5,531 21.81 0.0047
2025-05-29 2025-03-31 13F/A-1 RHYTHM PHARMACEUTICALS COM 76243J105 85,719 2,988 3.61 4,541 -1.97 0.0042
2025-04-08 2025-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 85,719 2,988 4,541 0.0042
2025-05-29 2024-12-31 13F/A-1 RHYTHM PHARMACEUTICALS COM 76243J105 82,731 2,017 2.50 4,631 9.53 0.0041
2025-01-30 2024-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 82,731 2,017 4,631 0.0041
2024-11-12 2024-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 80,714 -2,349 -2.83 4,229 23.99 0.0038
2024-08-01 2024-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 83,063 6,339 8.26 3,411 2.59 0.0032
2024-05-09 2024-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 76,724 3,552 4.85 3,324 -1.16 0.0032
2024-02-08 2023-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 73,172 -287 -0.39 3,364 99.70 0.0035
2023-11-09 2023-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 73,459 3,861 5.55 1,684 46.82 0.0020
2023-08-08 2023-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 69,598 69,598 1,148 0.0013
2022-08-11 2022-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 0 -56,942 -100.00 0 -100.00
2022-05-12 2022-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 56,942 -3,595 -5.94 656 8.61 0.0008
2022-02-10 2021-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 60,537 -750 -1.22 604 -24.50 0.0007
2021-11-12 2021-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 61,287 275 0.45 800 -33.05 0.0011
2021-08-05 2021-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 61,012 20,857 51.94 1,195 39.93 0.0016
2021-05-06 2021-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 40,155 -1,423 -3.42 854 -30.91 0.0012
2021-02-10 2020-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 41,578 2,865 7.40 1,236 47.32 0.0017
2020-11-12 2020-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 38,713 -5,915 -13.25 839 -15.68 0.0013
2020-08-13 2020-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 44,628 10,124 29.34 995 89.52 0.0017
2020-05-06 2020-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 34,504 2,109 6.51 525 -29.44 0.0011
2020-02-05 2019-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 32,395 6,542 25.30 744 33.33 0.0012
2019-10-23 2019-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 25,853 -240 -0.92 558 -2.79 0.0010
2019-08-14 2019-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 26,093 6,490 33.11 574 6.89 0.0011
2019-05-01 2019-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 19,603 50 0.26 537 2.09 0.0010
2019-01-31 2018-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 19,553 7,458 61.66 526 49.01 0.0011
2018-11-07 2018-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 12,095 661 5.78 353 -1.12 0.0007
2018-08-06 2018-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 11,434 11,434 357 0.0007
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.