Rhythm Pharmaceuticals, Inc.
US ˙ NasdaqGM ˙ US76243J1051

SecurityRYTM / Rhythm Pharmaceuticals, Inc.
InstitutionUBS Group AG
Latest Disclosed Ownership231,650 shares
Latest Disclosed Value $ 20,146,601
UBS Group AG ownership in RYTM / Rhythm Pharmaceuticals, Inc.

On May 5, 2026 - UBS Group AG filed a 13F-HR form disclosing ownership of 231,650 shares of Rhythm Pharmaceuticals, Inc. (US:RYTM) valued at $20,146,600 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 29, 2026 disclosing 427,236 shares of Rhythm Pharmaceuticals, Inc.. This represents a change in shares of -45.78% during the quarter. The current value of the position is $20,294,856 USD.

UBS Group AG has a history of taking positions in derivatives of the underlying security (RYTM) in the form of stock options. The firm currently holds call options representing 0 of underlying shares valued at $0 USD .

Note: prior versions of this page mistakenly stated that the share values represented the number of options, not the number of underlying shares. For more information on the data backing these reports, please see the SEC document Frequently Asked Questions About Form 13F.

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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Institutional Put/Call Ratios
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In addition to reporting standard equity and debt issues, institutions with more than 100MM assets under management must also disclose their put and call option holdings. Since put options generally indicate negative sentiment, and call options indicate positive sentiment, we can get a sense of the overall institutional sentiment by plotting the ratio of puts to calls. The chart to the right plots the historical put/call ratio for this instrument.

Using Put/Call Ratio as an indicator of investor sentiment overcomes one of the key deficiencies of using total institutional ownership, which is that a significant amount of assets under management are invested passively to track indices. Passively-managed funds do not typically buy options, so the put/call ratio indicator more closely tracks the sentiment of actively-managed funds.

RYTM / Rhythm Pharmaceuticals, Inc. Historical Put/Call Ratio
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)
2026-05-05 2026-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 231,650 -195,586 -45.78 20,147 -55.95 0.0006
2026-01-29 2025-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 427,236 6,900 1.64 45,731 7.73 0.0074
2025-11-13 2025-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 420,336 167,754 66.42 42,450 165.97 0.0066
2025-08-14 2025-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 252,582 -19,526 -7.18 15,961 10.73 0.0028
2025-05-13 2025-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 272,108 17,844 7.02 14,414 1.26 0.0026
2025-02-14 2024-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 254,264 177,630 231.79 14,234 254.58 0.0026
2024-11-14 2024-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 76,634 10,692 16.21 4,015 48.28 0.0009
2024-08-14 2024-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 65,942 -105,623 -61.56 2,708 -63.58 0.0007
2024-05-13 2024-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 171,565 85,610 99.60 7,434 88.13 0.0019
2024-02-09 2023-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 85,955 59,304 222.52 3,951 547.70 0.0012
2023-11-09 2023-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 26,651 -61,198 -69.66 611 -57.87 0.0002
2023-08-11 2023-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 87,849 3,772 4.49 1,449 -3.40 0.0005
2023-05-12 2023-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 84,077 -107,188 -56.04 1,500 -73.08 0.0005
2023-02-08 2022-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 191,265 178,630 1,413.77 5,570 1,702.27 0.0021
2022-11-10 2022-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 12,635 5,128 68.31 309 896.77 0.0001
2022-08-10 2022-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 7,507 7,007 1,401.40 31 416.67 0.0000
2022-05-16 2022-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 500 -103,080 -99.52 6 -99.42 0.0000
2022-02-14 2021-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 103,580 22,610 27.92 1,034 -2.27 0.0003
2021-11-15 2021-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 80,970 851 1.06 1,058 -32.53 0.0003
2021-08-13 2021-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 80,119 -46,731 -36.84 1,568 -41.88 0.0005
2021-05-12 2021-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 126,850 25,699 25.41 2,698 -10.28 0.0009
2021-02-11 2020-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 101,151 58,894 139.37 3,007 228.28 0.0010
2020-11-12 2020-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 42,257 42,011 17,077.64 916 18,220.00 0.0003
2020-07-31 2020-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 246 -5,579 -95.78 5 -94.38 0.0000
2020-05-01 2020-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 5,825 4,084 234.58 89 122.50 0.0000
2020-02-14 2019-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 1,741 -33,231 -95.02 40 -94.70 0.0000
2019-11-14 2019-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 34,972 34,216 4,525.93 755 4,341.18 0.0003
2019-08-14 2019-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 756 570 306.45 17 240.00 0.0000
2019-05-14 2019-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 186 -10,178 -98.21 5 -98.21 0.0000
2019-02-14 2018-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 10,364 5,408 109.12 279 92.41 0.0001
2018-11-14 2018-09-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 4,956 2,389 93.07 145 81.25 0.0001
2018-08-14 2018-06-30 13F RHYTHM PHARMACEUTICALS COM 76243J105 2,567 1,624 172.22 80 321.05 0.0000
2018-05-15 2018-03-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 943 -7,909 -89.35 19 -92.61 0.0000
2018-02-14 2017-12-31 13F RHYTHM PHARMACEUTICALS COM 76243J105 8,852 8,852 257 0.0001
Disclosed Call Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share
Price
Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2025-08-14 2025-06-30 13F RHYTHM PHARMACEUTICALS COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2025-05-13 2025-03-31 13F RHYTHM PHARMACEUTICALS COM Call 8,100 429 n/a n/a n/a
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.