---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-25-284609"
form_type: "8-K"
ticker: "IONS"
cik: "0000874015"
company_name: "IONIS PHARMACEUTICALS INC"
filed_at: "2025-11-17T23:59:59+00:00"
generated_at: "2026-05-16T19:34:27.231107+00:00"
event_type: "debt"
sentiment: "neutral"
materiality_score: 0.75
calibrated_materiality_score: 0.75
confidence: "high"
source: SEC EDGAR
---

# Ionis closes $770M 0% convertible notes offering, repurchases $200M of 2026 notes

## Summary
- Issued $770M aggregate principal of 0.00% Convertible Senior Notes due 2030 (including full greenshoe), net proceeds ~$751.2M.
- Used ~$267.6M of net proceeds to repurchase $200M of existing 2026 convertible notes via concurrent transactions.
- Remaining proceeds for further repurchases of 2026 notes and general corporate purposes.
- Initial conversion rate: 10.1932 shares/$1,000, conversion price ~$98.10 (35% premium over Nov 12 close of $72.67).
- Notes mature Dec 1, 2030, no regular interest, redeemable after Dec 6, 2028 if stock ≥130% of conversion price.

## SEC filing metadata
- accession: 0001193125-25-284609
- form_type: 8-K
- ticker: IONS
- cik: 0000874015
- company_name: IONIS PHARMACEUTICALS INC
- filed_at: 2025-11-17T23:59:59+00:00
- event_type: debt
- sentiment: neutral
- materiality_score: 0.75
- calibrated_materiality_score: 0.75
- confidence: high
- sec_items: 1.01, 2.03, 3.02, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/874015/000119312525284609/0001193125-25-284609-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/874015/000119312525284609/d31230d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-25-284609
- JSON: https://secwatch.observer/filing/0001193125-25-284609.json
- Plain text: https://secwatch.observer/filing/0001193125-25-284609.txt

## Key facts
- Debt Financings
  IONIS PHARMACEUTICALS INC incurred convertible notes of $770.0 million aggregate principal amount with U.S. Bank Trust Company, National Association at 0.00% maturing December 1, 2030.
  - Instrument: convertible notes
  - Principal: $770.0 million aggregate principal amount
  - Counterparty: U.S. Bank Trust Company, National Association
  - Rate: 0.00%
  - Maturity: December 1, 2030
  - Event: incurrence
  source text: On November 17, 2025, Ionis Pharmaceuticals, Inc. (the “Company”) completed its previously announced private offering (the “Offering”) of $770.0 million aggregate principal amount of 0.00% Convertible Senior Notes due 2030 (the “Notes”), including the exercise in full of the initial purchasers’ option to purchase up to an additional $70.0 million principal amount of Notes.
  evidence_url: https://www.sec.gov/Archives/edgar/data/874015/000119312525284609/0001193125-25-284609-index.htm
- Equity Issuances
  IONIS PHARMACEUTICALS INC issued convertible note to initial purchasers for $770.0 million aggregate principal amount.
  - Security: convertible note
  - Purchaser: initial purchasers
  - Consideration: $770.0 million aggregate principal amount
  source text: On November 17, 2025, Ionis Pharmaceuticals, Inc. (the “Company”) completed its previously announced private offering (the “Offering”) of $770.0 million aggregate principal amount of 0.00% Convertible Senior Notes due 2030 (the “Notes”), including the exercise in full of the initial purchasers’ option to purchase up to an additional $70.0 million principal amount of Notes.
  evidence_url: https://www.sec.gov/Archives/edgar/data/874015/000119312525284609/0001193125-25-284609-index.htm

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