Larimar Therapeutics, Inc.
US ˙ NasdaqGM ˙ US5171251003

SecurityLRMR / Larimar Therapeutics, Inc.
InstitutionDeerfield Management Company, L.p. (series C)
Latest Disclosed Ownership35,606,974 shares
Latest Disclosed Value $ 160,231,383
Deerfield Management Company, L.p. (series C) reports 16.34% increase in ownership of LRMR / Larimar Therapeutics, Inc.

On May 15, 2026 - Deerfield Management Company, L.p. (series C) filed a 13F-HR form disclosing ownership of 35,606,974 shares of Larimar Therapeutics, Inc. (US:LRMR) valued at $160,231,383 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 30,606,974 shares of Larimar Therapeutics, Inc.. This represents a change in shares of 16.34% during the quarter. The current value of the position is $113,942,317 USD.

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 LARIMAR THERAPEUTICS COM 517125100 35,606,974 5,000,000 16.34 160,231 37.41 1.8903
2026-02-17 2025-12-31 13F LARIMAR THERAPEUTICS COM 517125100 30,606,974 0 0.00 116,613 17.96 1.4893
2025-11-14 2025-09-30 13F LARIMAR THERAPEUTICS COM 517125100 30,606,974 9,375,000 44.16 98,861 61.11 1.5092
2025-08-14 2025-06-30 13F LARIMAR THERAPEUTICS COM 517125100 21,231,974 0 0.00 61,360 34.42 1.1137
2025-05-15 2025-03-31 13F LARIMAR THERAPEUTICS COM 517125100 21,231,974 0 0.00 45,649 -44.44 0.9013
2025-02-14 2024-12-31 13F LARIMAR THERAPEUTICS COM 517125100 21,231,974 0 0.00 82,168 -40.92 1.5562
2024-11-14 2024-09-30 13F LARIMAR THERAPEUTICS COM 517125100 21,231,974 0 0.00 139,069 -9.65 2.0779
2024-08-14 2024-06-30 13F LARIMAR THERAPEUTICS COM 517125100 21,231,974 0 0.00 153,932 -4.48 2.5610
2024-05-15 2024-03-31 13F LARIMAR THERAPEUTICS COM 517125100 21,231,974 4,290,617 25.33 161,151 109.06 2.8036
2024-02-14 2023-12-31 13F LARIMAR THERAPEUTICS COM 517125100 16,941,357 0 0.00 77,083 15.19 1.4233
2023-11-14 2023-09-30 13F LARIMAR THERAPEUTICS COM 517125100 16,941,357 0 0.00 66,918 26.20 1.4744
2023-08-14 2023-06-30 13F LARIMAR THERAPEUTICS COM 517125100 16,941,357 0 0.00 53,026 -30.91 1.1320
2023-05-15 2023-03-31 13F LARIMAR THERAPEUTICS COM 517125100 16,941,357 0 0.00 76,744 9.69 1.7109
2023-02-14 2022-12-31 13F LARIMAR THERAPEUTICS COM 517125100 16,941,357 0 0.00 69,968 29.06 1.4483
2022-11-14 2022-09-30 13F LARIMAR THERAPEUTICS COM 517125100 16,941,357 11,111,108 190.58 54,212 374.42 1.0791
2022-08-15 2022-06-30 13F LARIMAR THERAPEUTICS COM 517125100 5,830,249 0 0.00 11,427 -51.61 0.2357
2022-05-16 2022-03-31 13F LARIMAR THERAPEUTICS COM 517125100 5,830,249 0 0.00 23,613 -62.46 0.5279
2022-02-14 2021-12-31 13F LARIMAR THERAPEUTICS COM 517125100 5,830,249 0 0.00 62,908 -6.42 1.3195
2021-11-15 2021-09-30 13F LARIMAR THERAPEUTICS COM 517125100 5,830,249 0 0.00 67,223 17.41 1.3119
2021-08-16 2021-06-30 13F LARIMAR THERAPEUTICS COM 517125100 5,830,249 685,710 13.33 57,253 -23.83 1.0170
2021-05-17 2021-03-31 13F LARIMAR THERAPEUTICS COM 517125100 5,144,539 0 0.00 75,162 -31.76 1.5796
2021-02-16 2020-12-31 13F LARIMAR THERAPEUTICS COM 517125100 5,144,539 0 0.00 110,145 41.13 2.1769
2020-12-30 2020-09-30 13F/A-1 LARIMAR THERAPEUTICS COM 517125100 5,144,539 0 0.00 78,043 18.06 1.9003
2020-11-16 2020-09-30 13F LARIMAR THERAPEUTICS COM 517125100 5,144,539 0 78,043 1,900,283.2784
2020-08-14 2020-06-30 13F LARIMAR THERAPEUTICS COM 517125100 5,144,539 5,144,539 66,107 1.9251
2016-11-14 2016-09-30 13F ZAFGEN COM 98885E103 0 -3,055,603 -100.00 0 -100.00
2016-08-15 2016-06-30 13F ZAFGEN COM 98885E103 3,055,603 0 0.00 18,303 -10.33 0.7193
2016-05-16 2016-03-31 13F ZAFGEN COM 98885E103 3,055,603 2,211,938 262.18 20,411 284.61 0.8690
2016-02-16 2015-12-31 13F ZAFGEN COM 98885E103 843,665 290,193 52.43 5,307 -69.99 0.2151
2015-11-16 2015-09-30 13F ZAFGEN COM 98885E103 553,472 -454,142 -45.07 17,683 -49.32 0.6840
2015-08-14 2015-06-30 13F ZAFGEN COM 98885E103 1,007,614 -42,564 -4.05 34,894 -16.12 1.1625
2015-05-15 2015-03-31 13F ZAFGEN COM 98885E103 1,050,178 1,050,178 41,598 1.3478
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.