BOURNE 4 Isn't Really BOURNE But Will Be BOURNE Whether It Wants To Be Or Not!!

Merrick here...
During a CURIOUS CASE OF BENJAMIN BUTTON event, producer Frank Marshall revealed that the BOURNE Powers That Be may be close to zeroing in on a storyline for a proposed continuation of the BOURNE movie franchise. Seems they now have access to "all" Ludlum story ideas & intend to repurpose one of them into a new BOURNE adventure. Specifically...

Q: Would you want to do a straight adaptation from one of the novels? Marshall: Actually, there is. "The Parsifal Mosaic" is one that we like. "The Parsifal Mosiac," not a "Bourne" adventure as a novel, deals with a U.S. spy who falls in love with another spy who is revealed to be a double agent just before her death. When he retires from the business, though, the spy learns that she may still be alive and sets out to learn the truth.

...says THIS write-up at ComingSoon. You can find more about PARSIFAL via THIS Wiki entry.