About Sixth-Domain

Sixth-Domain is a database of defense and dual-use startups in Europe, the United States and allied nations, and the investors, programmes and opportunities around them. It is built for founders, investors, corporates and government buyers.

Sixth-Domain launched in October 2025. It was founded by Katherine Thomas, Co-Founder.

Startup data comes from official filings and registers, company websites, accelerator and programme announcements, and reputable news. Corrections are welcome via the contact page.

Startup database · Investor directory · Opportunities · Contact