Repligen Corporation
US ˙ NasdaqGS ˙ US7599161095

SecurityRGEN / Repligen Corporation
InstitutionMcIlrath & Eck, LLC
Latest Disclosed Ownership35 shares
Latest Disclosed Value $ 4,124
McIlrath & Eck, LLC ownership in RGEN / Repligen Corporation

On May 19, 2026 - McIlrath & Eck, LLC filed a 13F-HR form disclosing ownership of 35 shares of Repligen Corporation (US:RGEN) valued at $4,124 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 3, 2026 disclosing 35 shares of Repligen Corporation. This represents a change in shares of 0.00% during the quarter. The current value of the position is $4,261 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)
2026-05-19 2026-03-31 13F REPLIGEN CORP COM COMMON STOCK 759916109 35 0 0.00 4 -20.00 0.0003
2026-02-03 2025-12-31 13F REPLIGEN COM 759916109 35 0 0.00 6 25.00 0.0005
2025-10-22 2025-09-30 13F REPLIGEN OM 759916109 35 0 0.00 5 0.00 0.0005
2025-08-14 2025-06-30 13F REPLIGEN COM 759916109 35 0 0.00 4 0.00 0.0005
2025-05-16 2025-03-31 13F REPLIGEN COM 759916109 35 0 0.00 4 -20.00 0.0005
2025-02-18 2024-12-31 13F REPLIGEN COM 759916109 35 0 0.00 5 0.00 0.0006
2024-11-19 2024-09-30 13F REPLIGEN COM 759916109 35 0 0.00 5 25.00 0.0007
2024-08-14 2024-06-30 13F REPLIGEN COM 759916109 35 0 0.00 4 -33.33 0.0007
2024-05-10 2024-03-31 13F REPLIGEN COM 759916109 35 0 0.00 6 0.00 0.0010
2024-02-06 2023-12-31 13F REPLIGEN COM 759916109 35 0 0.00 6 20.00 0.0011
2023-11-16 2023-09-30 13F REPLIGEN COM 759916109 35 0 0.00 6 25.00 0.0011
2023-08-07 2023-06-30 13F REPLIGEN COM 759916109 35 0 0.00 5 -20.00 0.0010
2023-05-09 2023-03-31 13F REPLIGEN COM 759916109 35 0 0.00 6 0.00 0.0014
2023-02-15 2022-12-31 13F REPLIGEN COM 759916109 35 0 0.00 6 -28.57 0.0015
2022-10-18 2022-09-30 13F REPLIGEN COM 759916109 35 0 0.00 7 16.67 0.0019
2022-07-29 2022-06-30 13F REPLIGEN COM 759916109 35 0 0.00 6 -14.29 0.0019
2022-05-11 2022-03-31 13F REPLIGEN COM 759916109 35 0 0.00 7 -22.22 0.0020
2022-02-08 2021-12-31 13F REPLIGEN COM 759916109 35 0 0.00 9 -10.00 0.0024
2021-11-12 2021-09-30 13F REPLIGEN COM 759916109 35 0 0.00 10 42.86 0.0030
2021-08-09 2021-06-30 13F REPLIGEN COM 759916109 35 0 0.00 7 0.00 0.0021
2021-05-12 2021-03-31 13F REPLIGEN COM 759916109 35 35 7 0.0024
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.