In 2020, Proton was the victim of BGP hijacking. In a blog post about the incident, Proton said it was securing its own BGP route announcements using RPKI. However, Proton VPN's ISP (M247, AS9009) does not use RPKI to verify other sites' announcements. This can be seen by going to the Is BGP Safe Yet website Proton linked to in its own blog post. Proton should use RPKI to verify the routes to sites its customers visit so the customers are protected from BGP hijacking of the sites they visit.