I remember visiting MS (Redmond), in the 1990s (It was at the "Longhorn" launch, if that helps date it).

A friend of mine, worked in one of the nearby buildings, and took me to his office (He was doing documentation, or something for Encarta).

I was struck by the narrow, dark, corridors, and the small, windowless, offices. My friend said that all MS engineers had a private office.

I have since been told that the building I visited was probably an old one, and not representative of most buildings, and I think that MS went open-plan, since.

I have also visited the Facebook (it was still called Facebook, back then) office, in NYC.

The programming floor was a really big, noisy, open-plan office, jammed with desks (standing and sitting), and everyone was talking away. No windows. The floor was surrounded by conference rooms and offices, which had windows.

The Japanese offices of my own company were sort of like that, but with uniform desks, and quiet as a mouse; even with hundreds of people. No individual offices. VPs, with billion-dollar budgets, had a small desk, in the corner.

Microsoft started to transition to open layout company-wide sometime in the mid-10s. Depending on the org, some team at Microsoft still had private offices for their devs as late as 2017.

some still have (bing, some azure teams), though it ends soon.