---
schema_version: "secwatch.filing_event.v1"
accession: "0001628280-23-015503"
form_type: "8-K"
ticker: "ESPR"
cik: "0001434868"
company_name: "Esperion Therapeutics, Inc."
filed_at: "2023-05-04T23:59:59+00:00"
generated_at: "2026-06-15T21:34:01.641282+00:00"
event_type: "litigation"
sentiment: "negative"
materiality_score: 0.8
calibrated_materiality_score: 0.8
confidence: "high"
source: SEC EDGAR
---

# Esperion sues Daiichi Sankyo Europe over $300M milestone payment dispute

## Summary
- Filed amended complaint seeking declaration that DSE must pay $300M regulatory milestone upon cardiovascular risk reduction label.
- DSE informed Esperion on March 8, 2023 it would not make payment, citing MACE-4 result below 15%.
- Agreement requires payment for >20% risk reduction based on CLEAR Outcomes study; DSE's interpretation allegedly contradicts plain terms.
- Esperion claims DSE's repudiation caused 54% stock drop and is bad-faith attempt to renegotiate.
- Court in Southern District of New York; expedited declaratory judgment sought.

## SEC filing metadata
- accession: 0001628280-23-015503
- form_type: 8-K
- ticker: ESPR
- cik: 0001434868
- company_name: Esperion Therapeutics, Inc.
- filed_at: 2023-05-04T23:59:59+00:00
- event_type: litigation
- sentiment: negative
- materiality_score: 0.8
- calibrated_materiality_score: 0.8
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1434868/000162828023015503/0001628280-23-015503-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1434868/000162828023015503/espr-20230504.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001628280-23-015503
- JSON: https://secwatch.observer/filing/0001628280-23-015503.json
- Plain text: https://secwatch.observer/filing/0001628280-23-015503.txt

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