This could be accomplished by the concept of a "Lease." The Reader is granted, via the Owner, the ability to perform operations on the Data with a set of expiry conditions (time, usage count, etc). See Vanish.
Vanish was achieved by leveraging the BitTorrent DHT to decentralize the storage of data. However, Vanish was proven by a seperate group of researchs to be susceptible to Sybil Attacks ("UnVanish", https://news.utexas.edu/2009/09/29/new-digital-security-program-doesnt-protect-as-promised)