---
schema_version: "secwatch.filing_event.v1"
accession: "0001104659-26-075731"
form_type: "8-K"
ticker: "PTCT"
cik: "0001070081"
company_name: "PTC THERAPEUTICS, INC."
filed_at: "2026-06-18T20:14:58+00:00"
generated_at: "2026-06-18T20:22:00.124942+00:00"
event_type: "debt"
sentiment: "neutral"
materiality_score: 0.75
calibrated_materiality_score: 0.75
confidence: "high"
source: SEC EDGAR
---

# PTC Therapeutics closes $550M zero-coupon convertible notes offering, repurchases $222M of existing notes

## Summary
- Issued $550M aggregate principal of 0.0% Convertible Senior Notes due 2031, initial conversion price ~$107.48/share.
- Net proceeds approximately $535.5M after discounts and estimated offering expenses.
- Using ~$328.8M to repurchase $222M principal of existing 1.50% Convertible Senior Notes due 2026; $55.5M remains outstanding.
- Notes are general unsecured senior obligations; company may redeem after June 20, 2029 if stock price >=130% of conversion price.
- Initial purchasers exercised in full their option to purchase an additional $50M of notes.

## SEC filing metadata
- accession: 0001104659-26-075731
- form_type: 8-K
- ticker: PTCT
- cik: 0001070081
- company_name: PTC THERAPEUTICS, INC.
- filed_at: 2026-06-18T20:14:58+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/1070081/000110465926075731/0001104659-26-075731-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1070081/000110465926075731/tm2618266d1_8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001104659-26-075731
- JSON: https://secwatch.observer/filing/0001104659-26-075731.json
- Plain text: https://secwatch.observer/filing/0001104659-26-075731.txt

## Key facts
- Debt Financings
  PTC THERAPEUTICS, INC. incurred convertible notes of $550,000,000 with U.S. Bank Trust Company, National Association at 0.0% maturing June 15, 2031.
  - Instrument: convertible notes
  - Principal: $550,000,000
  - Counterparty: U.S. Bank Trust Company, National Association
  - Rate: 0.0%
  - Maturity: June 15, 2031
  - Event: incurrence
  source text: On June 18, 2026, PTC Therapeutics, Inc. (the “Company”) completed its previously announced private offering of $550,000,000 aggregate principal amount of its 0.0% Convertible Senior Notes due 2031 (the “Notes”) and entered into an indenture with U.S. Bank Trust Company, National Association, as trustee (the “Trustee”), governing the Notes (the “Indenture”).
  evidence_url: https://www.sec.gov/Archives/edgar/data/1070081/000110465926075731/0001104659-26-075731-index.htm
- Material Agreements
  PTC THERAPEUTICS, INC. entered into Indenture with U.S. Bank Trust Company, National Association valued at $550,000,000 0.0% Convertible Senior Notes due 2031 (effective 2026-06-18).
  - Action: entry
  - Agreement: notes offering
  - Counterparty: U.S. Bank Trust Company, National Association
  - Value: $550,000,000 0.0% Convertible Senior Notes due 2031
  - Effective: 2026-06-18
  source text: On June 18, 2026, PTC Therapeutics, Inc. (the “Company”) completed its previously announced private offering of $550,000,000 aggregate principal amount of its 0.0% Convertible Senior Notes due 2031 (the “Notes”) and entered into an indenture with U.S. Bank Trust Company, National Association, as trustee (the “Trustee”), governing the Notes (the “Indenture”).
  evidence_url: https://www.sec.gov/Archives/edgar/data/1070081/000110465926075731/0001104659-26-075731-index.htm

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