Based on the knowledge sources, Ory supports multiple authentication methods for the same user account, including passkeys. While there isn't explicit documentation stating that multiple passkeys can be registered for a single user account, the information suggests this is possible through several aspects of Ory's identity management: 1. Ory supports multiple credentials per identity. As shown in the identity schema documentation, you can configure multiple authentication methods for the same user traits, including passkeys:

json {   "traits": {     "type": "object",     "properties": {       "email": {         "type": "string",         "format": "email",         "<http://ory.sh/kratos|ory.sh/kratos>": {           "credentials": {             "password": {               "identifier": true             },             "webauthn": {               "identifier": true             },             "passkey": {               "display_name": true             }           }         }       }     }   } }

2. Ory supports cross-platform passkeys, allowing users to authenticate across multiple devices using the same key, which suggests flexibility in passkey management [Blog > Login and authentication in 2023 explained](https://www.ory.sh/blog/overview-login-password-passkey-webauthn-totp-sso-faceid). 3. The documentation discusses passkey sharing between devices and secure transfer of passkeys to new devices, indicating that multiple passkeys can be associated with a user account [Docs > Kratos > Passwordless](https://www.ory.sh/docs/kratos/passwordless/passwordless#logging-in-with-a-passkey-across-multiple-devices). However, it's worth noting that WebAuthn (the underlying technology for passkeys) has some constraints, particularly that it's domain-specific and doesn't work across multiple domains [Docs > Kratos > Passwordless > Passkeys & WebAuthN](https://www.ory.sh/docs/kratos/passwordless/passkeys#constraints). If you need more specific information about managing multiple passkeys for a single user account, you might want to consult the Ory documentation directly or contact Ory support.