Apparently "several" means three. How and why is this news? Microsoft has thousands of employees.
“Several” has long meant three or more, but the article says that three workers described the effort to Reuters, not that the three constituted the entire effort.
"Described to Reuters by three Microsoft workers" doesn't necessarily mean only three workers are involved in this protest. However I would be interested to see the actual numbers. If the number of employees signing the petition were impressive, I'd expect it to be prominently reported. Since it's not, that leads me to suspect it's not very much more than three.
I did - and more fool me, perhaps. But I clicked. And that's all that counts.