---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-22-243702"
form_type: "8-K"
ticker: "ALNY"
cik: "0001178670"
company_name: "ALNYLAM PHARMACEUTICALS, INC."
filed_at: "2022-09-13T23:59:59+00:00"
generated_at: "2026-06-23T09:56:02.280038+00:00"
event_type: "debt"
sentiment: "neutral"
materiality_score: 0.6
calibrated_materiality_score: 0.6
confidence: "high"
source: SEC EDGAR
---

# Alnylam prices $900M convertible senior notes at 1.00% due 2027; conversion premium 35%

## Summary
- Principal $900M (greenshoe up to $135M); interest 1.00% semi-annual; maturity Sept 15, 2027.
- Initial conversion price ~$286.20/share, 35% premium over $212.00 close on Sept 12, 2022.
- Net proceeds est. $883.2M (or $1,015.8M with greenshoe); $762M to repay credit facility, $103.1M for capped call.
- Capped call cap price $424.00/share, reducing dilution upon conversion; counterparties may hedge in open market.
- Offering expected to close Sept 15, 2022, subject to customary conditions.

## SEC filing metadata
- accession: 0001193125-22-243702
- form_type: 8-K
- ticker: ALNY
- cik: 0001178670
- company_name: ALNYLAM PHARMACEUTICALS, INC.
- filed_at: 2022-09-13T23:59:59+00:00
- event_type: debt
- sentiment: neutral
- materiality_score: 0.6
- calibrated_materiality_score: 0.6
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1178670/000119312522243702/0001193125-22-243702-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1178670/000119312522243702/d397120d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-22-243702
- JSON: https://secwatch.observer/filing/0001193125-22-243702.json
- Plain text: https://secwatch.observer/filing/0001193125-22-243702.txt

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