Olivier Loeillot - 20 Aug 2026 Form 4 Insider Report for REPLIGEN CORP (RGEN)

Reporting relationship: Chief Executive Officer, Director
Issuer ticker: RGEN
Reported as of: 20 Aug 2026
Net transaction value: -$976,680
SEC form: 4
Accepted by SEC: 21 Aug 2026, 16:06:30 UTC
Prior SEC filing: 22 Apr 2026
Source filing: View source filing
Reporting owner signature: /s/ Jennifer Carmichael (Attorney in Fact)

Key filing fact

Olivier Loeillot filed Form 4 for REPLIGEN CORP (RGEN) on 21 Aug 2026.

Key facts

This page summarizes Olivier Loeillot's Form 4 filing for REPLIGEN CORP (RGEN).
3 reported transactions and 1 derivative row are listed below.
Accepted by SEC: 21 Aug 2026, 16:06.

Change

Previous filing in this sequence was filed on 22 Apr 2026.
Current net transaction value: -$976,680.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001995525 Primary reporting owner

Loeillot Olivier

Relationship: Chief Executive Officer, Director
Address: C/O REPLIGEN CORPORATION, 41 SEYON ST., BLDG 1, STE 100, WALTHAM
Signature: /s/ Jennifer Carmichael (Attorney in Fact)
Signature date: 21 Aug 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

RGEN transaction

Common Stock

Options Exercise

Transaction value
Shares: +5,426
Change %: +10%
Price: $141.79^*
Shares after: 59,672
Date: 20 Aug 2026
Ownership: Direct
Footnotes: F1

RGEN transaction

Common Stock

Sale

Transaction value: $976,680
Shares: -5,426
Change %: -9.1%
Price: $180.00
Shares after: 54,246
Date: 20 Aug 2026
Ownership: Direct
Footnotes: F1

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

RGEN transaction Derivative

Stock Option (Right to Buy)

Options Exercise

Transaction value
Shares: -5,426
Change %: -33%
Price: $0.000000^*
Shares after: 10,852
Date: 20 Aug 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 5,426
Exercise price: $141.79
Footnotes: F1, F2

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Rule 10b5-1 trading plan

These transactions were reported as open-market trades under a Rule 10b5-1 plan. The plan lets an insider set trading instructions in advance, which can reduce the risk of trading while in possession of material nonpublic information.

Original filing language: transaction made pursuant to a contract, instruction, or written plan intended to satisfy Rule 10b5-1(c).

Explanation of responses 2 footnotes

Footnote F1

The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on August 19, 2025.

Footnote F2

5,426 shares will vest on each of September 3, 2026, and September 3, 2027.