Not sure how this stacks up against MS, but Google's research is posted here: https://research.google.com/pubs/papers.html
If you go by publication count alone, I suspect that IBM Research is still near the top. They have a large research organization that made some fundamental contributions in computer science in everything from speech recognition to databases.
Using the second metric, the winner in all cases - without negotiation - would be AT&T Bell Labs.
I'd also remind you of the cost of a telephone system with monopoly status that didn't even let you install your own phones in the house for a long time. And which led too skits like Lily Tomlin's "We don't care. We don't have to. We're the phone company."