Tresorit

Tresorit is a Budapest-founded end-to-end encrypted cloud storage and file-collaboration company that positioned itself very early as the privacy-first European alternative to Dropbox and Google Drive for regulated industries: law firms, healthcare, financial services, and — notably — government and defense teams in Europe that cannot legally store sensitive files with US hyperscalers. Founded in 2011 by István Lám, Szilveszter Szebeni, and György Szilágyi, the product is built around zero-knowledge client-side encryption, so files are encrypted before they leave the user's device and Tresorit itself cannot read them even if compelled.