James Bylund - 05 Mar 2026 Form 4 Insider Report for REPLIGEN CORP (RGEN)

Reporting relationship: Chief Operating Officer
Issuer ticker: RGEN
Reported as of: 05 Mar 2026
Net transaction value: $0
SEC form: 4
Accepted by SEC: 23 Mar 2026, 11:53:02 UTC
Prior SEC filing: 05 Mar 2026
Source filing: View source filing
Reporting owner signature: /s/ Jennifer Carmichael (Attorney in Fact)

Key filing fact

James Bylund filed Form 4 for REPLIGEN CORP (RGEN) on 23 Mar 2026.

Key facts

This page summarizes James Bylund's Form 4 filing for REPLIGEN CORP (RGEN).
2 reported transactions and 1 derivative row are listed below.
Accepted by SEC: 23 Mar 2026, 11:53.

Change

Previous filing in this sequence was filed on 05 Mar 2026.
Current net transaction value: $0.

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 0001849642 Primary reporting owner

Bylund James

Relationship: Chief Operating Officer
Address: C/O REPLIGEN CORPORATION, 41 SEYON ST., BLDG 1, STE 100, WALTHAM
Signature: /s/ Jennifer Carmichael (Attorney in Fact)
Signature date: 23 Mar 2026

Reported non-derivative transactions

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

RGEN transaction

Common Stock

Award

Transaction value
Shares: +7,751
Change %: +44%
Price: $0.000000^*
Shares after: 25,423
Date: 05 Mar 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)

Award

Transaction value
Shares: +8,315
Change %
Price: $0.000000^*
Shares after: 8,315
Date: 05 Mar 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 8,315
Exercise price: $141.91
Footnotes: F2

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

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 2 footnotes

Footnote F1

Mr. Bylund was awarded 7,751 restricted stock units. Each restricted stock unit represents a contingent right to receive one share of Repligen Corporation's Common Stock. The restricted stock units vest in equal annual instalments over a three-year period beginning on the first anniversary of the grant date. The restricted stock units may be settled only by delivering shares of Repligen Corporation's Common Stock, and thus, the grant is being reported in Table 1 as allowed per SEC guidance.

Footnote F2

One third of the stock options will vest and become exercisable annually on March 5, 2027, March 5, 2028, and March 5, 2029.