← Back to PeopleGGFounderGuillaume GenthialCo-Founder at FragmentLinkedInWebsiteCo-founder of Fragment, a startup from Y Combinator S23 batch.1Mentions1Articles1OutletsCompanies CoveredCigna1Fragment1Next1Opera Tech1Receptive AI1Sierra1Singtel1ArticlesMost recent firstMentioned InReferenced in coverageSierra acquired Paris-based, YC-backed FragmentSubstackpositiveApr 26, 2026“Co-founder of Paris-based Fragment acquired by Sierra, bringing expertise in building human-centered AI experiences to Sierra.”