Bell Labs was massive. It had 11,000 people who were involved in pretty much every nukes and cranny ranging from cosmology to transistors to UNIX. Microsoft research probably comes closest to modern equivalent of Bell Labs and it has only 1000 people. So Bell Labs was like 10 MSR combined in to one!
It's really a pity we don't have anything like Bell Labs any more even though profits have grown by leaps and bound. As it is investors would be more than happy to shutdown something like MSR and constantly force the company to "justify" its existence.
I don't know if it's an entirely fair comparison to go by body count. Things have gotten a lot more efficient since the Bell Labs days. Even Richard Hamming stated "when I first started working there was a woman who walked around handing out the coffee and donuts, now a machine does that and her job no longer exists."
Sure but we are talking about Bell labs organizational structure - I haven't heard Microsoft doing such a thing in their R&D - I'd be interested to know if I'm wrong on this actually.