US Patent 9172694 Propagating delegated authorized credentials through legacy systems

An approach is provided to access resources at legacy systems. In this approach, a resource request destined to a legacy system is receiving from a requestor with the resource request including an access token and being on behalf of a resource owner. A validation process is performed on the access token. If the access token is valid, the approach identifies the resource owner and one or more legacy access tokens used to access the legacy system. Another request is formed with the new request including the legacy access tokens. The new request is transmitted to the legacy system and a response is received back from the legacy system. The response received from the legacy system is transmitted back to the requestor.