After a series of stunning reports from the Guardian's Glenn Greenwald on the NSA's data collection programs, the paper will no doubt remain a central figure in the story of Edward Snowden, the whistleblower who leaked the PRISM slides in the first place. But, according to one of the reporters by-lined on the Washington Post's PRISM story, the exclusive was theirs to lose: it was offered to them first. 

Barton Gellman posted a story cobbled from his chat transcripts with Snowden late Sunday, which contained this exchange concerning the whistleblower's conditions to keep the story the Post's

To effect his plan, Snowden asked for a guarantee that The Washington Post would publish — within 72 hours — the full text of a PowerPoint presentation describing PRISM, a top-secret surveillance program that gathered intelligence from Microsoft, Facebook, Google and other Silicon Valley giants. He also asked that The Post publish online a cryptographic key that he could use to prove to a foreign embassy that he was the document’s source.

I told him we would not make any guarantee about what we published or when. (The Post broke the story two weeks later, on Thursday. The Post sought the views of government officials about the potential harm to national security prior to publication and decided to reproduce only four of the 41 slides.)

Snowden replied succinctly, “I regret that we weren’t able to keep this project unilateral.” Shortly afterward he made contact with Glenn Greenwald of the British newspaper the Guardian.

Although the Guardian and the Post published nearly simultaneously on the PRISM story, it looks like the Post may have beaten the Guardian, only just, in getting the story live. But Snowden has apparently given everything else to the Guardian: They broke the Verizon data collection story. They were tasked with, at his request, revealing his identity. In the end, notably, neither paper published the slides in their entirety. 

Gellman continued to chat with Snowden — codename "Verax," — after losing the exclusive, and his take on the conversation is worth a read. For one thing, it makes it clear that Snowden knew what he was getting in to, and that, arguably, his plan to reveal his identity after handing over the documents was as important to him as the leak itself.