US Patent 9548976 Facilitating single sign-on to software applications

After an initial user sign-on with an identity provider, and in response to an intention of the user to use a third-party application executing on a client device of the user and requiring user sign-on, the identity provider provides a client script to the third-party application. The client script facilitates user and application authentication and invokes a trusted broker application that interacts with the identity provider to enable the user to use the third-party application. The use of the trusted broker application provided by the identity provider frees the authors of third-party applications from the need to modify their applications to explicitly sign in with the identify provider.