As my colleague Claire Cain Miller and others have reported, some people with knowledge of the discussions said that Yelp walked away. The reason Yelp abandoned a seemingly sweet deal was never fully explained.
Now another person who was briefed on the negotiations said that it was Google that walked away. The person said that Google executives believed that their counterparts at Yelp weren't being "transparent." The executives also didn't want to let the negotiations be driven by leaks to the press, the person said, implying that it was Yelp that had first leaked word of the talks.