Patent ID: 8769627

Claim:
A computer-implemented method for validating ownership of deduplicated data, at least a portion of the method being performed by a computing device comprising at least one processor, the method comprising: identifying a request from a remote client to store a data object in a data store that already comprises an instance of the data object; in response to the request, verifying that the remote client possesses the data object by issuing, to the remote client: a random offset; a random value that is different than the random offset; a randomized challenge, the randomized challenge comprising a request for an authentication token demonstrating possession of the data object, the authentication token comprising a hash of a combination of the random value and a random sample of the data object, wherein the random sample is based on the random offset; in response to the randomized challenge, receiving the authentication token from the remote client; in response to receiving the authentication token from the remote client, storing the data object in the data store on behalf of the remote client.