I think it applies only to aids for specific companies? e.g. if all companies that satisfies some requirements (e.g. N number of employees/new jobs , specific geographic area, industry etc.) cam receive the aid it's legal.
This said, if the incentives are tailored a bit too much (i.e. there is clearly only one company that satisfies the prerequisites), it could be challenged as state aid. You still need someone to start the challenge though - either a competing company or a Commissioner.
