GP is from the UK. In British English, collective nouns (companies, sports teams, etc.) are treated as plural, and use the plural forms of verbs--hence "Microsoft have" and "Google don't".
In American English, collective nouns are treated as singular, in which case "Microsoft has" and "Google doesn't" would be correct. Unless the noun itself is plural (e.g., "the Atlanta Braves"), in which case the verbs are usually (but not always) plural.
It's like honor vs. honour, or color vs. colour. Either is correct, but you should be consistent with your usage.
The origin of this difference was once explained to me as being a result of the American Civil War. Previous to the war, plural collectives (as in British English) were used, and it was common to see "the United States are", since state identity was still important, and the prevailing mindset was one of a loose collection of independent states (albeit a little tighter than under the Articles of Confederation).
After the Civil War, the idea of the US as a single unified country was reinforced, hence "the United States is". This bled over into everyday speech.
I have not independently verified this, however.