節奏製藥公司
MX ˙ BMV ˙ US76243J1051
SecurityMX:RYTM / Rhythm Pharmaceuticals, Inc.
InstitutionMarshall Wace, Llp
Latest Disclosed Ownership9,628 shares
Latest Disclosed Value $ 837,347
Marshall Wace, Llp ownership in RYTM / Rhythm Pharmaceuticals, Inc.

On May 14, 2026 - Marshall Wace, Llp filed a 13F-HR form disclosing ownership of 9,628 shares of Rhythm Pharmaceuticals, Inc. (MX:RYTM) valued at $837,347 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 0 shares of Rhythm Pharmaceuticals, Inc..

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)
2026-05-14 2026-03-31 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 9,628 9,628 837 0.0004
2026-02-13 2025-12-31 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 0 -171,834 -100.00 0 -100.00
2025-11-13 2025-09-30 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 171,834 -204,408 -54.33 17,354 -27.01 0.0176
2025-08-13 2025-06-30 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 376,242 -158,861 -29.69 23,775 -16.12 0.0268
2025-05-15 2025-03-31 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 535,103 -157,700 -22.76 28,344 -26.92 0.0360
2025-02-13 2024-12-31 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 692,803 286,188 70.38 38,783 82.06 0.0466
2024-11-14 2024-09-30 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 406,615 299,806 280.69 21,303 385.79 0.0259
2024-08-14 2024-06-30 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 106,809 87,059 440.81 4,386 412.87 0.0059
2024-05-15 2024-03-31 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 19,750 19,750 856 0.0013
2024-02-14 2023-12-31 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 0 -34,494 -100.00 0 -100.00
2023-11-14 2023-09-30 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 34,494 -1,877 -5.16 791 31.89 0.0016
2023-08-14 2023-06-30 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 36,371 -57,475 -61.24 600 -64.22 0.0012
2023-05-15 2023-03-31 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 93,846 72,563 340.94 1,674 170.44 0.0036
2023-02-14 2022-12-31 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 21,283 21,283 620 0.0014
2021-08-13 2021-06-30 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 0 -178,757 -100.00 0 -100.00
2021-05-17 2021-03-31 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 178,757 159,599 833.07 3,802 567.02 0.0174
2021-02-16 2020-12-31 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 19,158 -9,034 -32.04 570 -6.71 0.0031
2020-11-16 2020-09-30 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 28,192 17,935 174.86 611 166.81 0.0039
2020-08-13 2020-06-30 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 10,257 10,257 -63.62 229 -62.52 0.0016
2020-02-14 2019-12-31 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 0 -2,298 -100.00 0 -100.00
2019-11-14 2019-09-30 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 2,298 2,298 50 0.0004
2019-08-14 2019-06-30 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 0 -14,715 -100.00 0 -100.00
2019-05-29 2019-03-31 13F/A-1 RHYTHM PHARMACEU COMMON STOCK 76243J105 14,715 12,417 540.34 403 550.00 0.0038
2019-05-14 2019-03-31 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 14,715 12,417 403
2019-02-14 2018-12-31 13F RHYTHM PHARMACEU COMMON STOCK 76243J105 2,298 2,298 62 0.0006
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.