The complaints were brought up by a company called Elegant Business SC, who complained to the National Competition Commission that Microsoft allegedly prevented/unreasonably restricted the resale of software licenses. The information collected by the National Competition Commission was enough for them to launch an antitrust investigation that covers not just Spain, but in Ireland as well, which is where Microsoft’s European operations center is based.
The investigation has been given a deadline of 18 months, and with the heavy fines that Microsoft ended up paying in the past, it will be interesting to see if they will end up paying a fine again.