---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-23-301190"
form_type: "8-K"
ticker: "ANNX"
cik: "0001528115"
company_name: "Annexon, Inc."
filed_at: "2023-12-21T23:59:59+00:00"
generated_at: "2026-06-07T09:01:42.514920+00:00"
event_type: "other_material"
sentiment: "negative"
materiality_score: 0.8
calibrated_materiality_score: 0.8
confidence: "high"
source: SEC EDGAR
---

# Annexon prices $125M underwritten offering of common stock and pre-funded warrants

## Summary
- Gross proceeds expected ~$125M from 25,035,000 shares at $2.880 and 18,379,861 pre-funded warrants at $2.879.
- Closing expected December 26, 2023; Jefferies and TD Cowen act as joint book-running managers.
- Pre-funded warrants exercisable immediately; holder limited to 9.99% beneficial ownership unless increased.
- Offering dilutes existing shareholders; shares and warrants represent ~43M shares if fully exercised.

## SEC filing metadata
- accession: 0001193125-23-301190
- form_type: 8-K
- ticker: ANNX
- cik: 0001528115
- company_name: Annexon, Inc.
- filed_at: 2023-12-21T23:59:59+00:00
- event_type: other_material
- sentiment: negative
- materiality_score: 0.8
- calibrated_materiality_score: 0.8
- confidence: high
- sec_items: 1.01, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1528115/000119312523301190/0001193125-23-301190-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1528115/000119312523301190/d456025d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-23-301190
- JSON: https://secwatch.observer/filing/0001193125-23-301190.json
- Plain text: https://secwatch.observer/filing/0001193125-23-301190.txt

## Key facts
- Material Agreements
  Annexon, Inc. entered into Underwriting Agreement with Jefferies LLC and Cowen and Company, LLC valued at approximately $125.0 million (effective 2023-12-20).
  - Action: entry
  - Agreement: underwriting
  - Counterparty: Jefferies LLC and Cowen and Company, LLC
  - Value: approximately $125.0 million
  - Effective: 2023-12-20
  source text: On December 20, 2023, Annexon, Inc. (the “C ompan y’) entered into an underwriting agreement (“ Underwriting Agreement ”) with Jefferies LLC and Cowen and Company, LLC (the “ Underwriters ”), to issue and sell 25,035,000 shares (the “ Shares ”) of the Company’s common stock, par value $0.001 per share (the “ Common Stock ”) at a price of $2.880 per share
  evidence_url: https://www.sec.gov/Archives/edgar/data/1528115/000119312523301190/0001193125-23-301190-index.htm

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