---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-26-085368"
form_type: "8-K"
ticker: "MCRB"
cik: "0001609809"
company_name: "Seres Therapeutics, Inc."
filed_at: "2026-03-02T23:59:59+00:00"
generated_at: "2026-05-15T22:39:49.944488+00:00"
event_type: "leadership"
sentiment: "neutral"
materiality_score: 0.65
calibrated_materiality_score: 0.65
confidence: "high"
source: SEC EDGAR
---

# Seres Therapeutics appoints Richard Kender as Interim CEO, effective March 2

## Summary
- Thomas DesRosier and Marella Thorell step down as co-Presidents/co-CEOs but remain EVP CLO and EVP CFO.
- Kender receives $520K base salary, $250K signing bonus, and options for 200,000 shares.
- Matthew Henn named President (in addition to CSO); salary increased to $505K, $230K retention bonus.
- Kelly Brady promoted to EVP COO; salary $475K, $230K retention bonus, options for 75,000 shares.

## SEC filing metadata
- accession: 0001193125-26-085368
- form_type: 8-K
- ticker: MCRB
- cik: 0001609809
- company_name: Seres Therapeutics, Inc.
- filed_at: 2026-03-02T23:59:59+00:00
- event_type: leadership
- sentiment: neutral
- materiality_score: 0.65
- calibrated_materiality_score: 0.65
- confidence: high
- sec_items: 5.02, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1609809/000119312526085368/0001193125-26-085368-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1609809/000119312526085368/d13425d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-26-085368
- JSON: https://secwatch.observer/filing/0001193125-26-085368.json
- Plain text: https://secwatch.observer/filing/0001193125-26-085368.txt

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.