You said "were" part of PRISM, so I thought you were thinking of the related MUSCULAR program, where "GCHQ and the NSA have secretly broken into the main commun

You said "were" part of PRISM, so I thought you were thinking of the related MUSCULAR program, where "GCHQ and the NSA have secretly broken into the main communications links that connect the data centers of Yahoo! and Google" (https://en.wikipedia.org/wiki/MUSCULAR https://en.wikipedia.org/wiki/MUSCULAR). Presumably Google's deployment of TLS for internal traffic after the Snowden leaks put an end to that. If you're thinking of PRISM itself, I'm not sure in what sense Google is "part of" it? Google sometimes provides data in response to court orders, but there's not much they can do about that.