Hello, I´ve realised that a competitor has placed 2 similiar ads in the first page of a keyword search. He´s modified the ad title and the phone adding spaces between numbers. Can I do the same or is that strategy prohibited by google?
No, you should report him. Bur first check does this ads land on same landing page (URL). Then file complaint to Google. Regards.
I think your competitor has two separate domains and running campaigns for those domains. Google doesn't allow multiple accounts to serve same ads and if someone does so his account will be terminated.
Think you should report this eitherway (separate domains or not), if its the same advertiser trying to buy ad space in the same ad auction hence gain an unfair advantage over other advertisers you should be able to make a case.