[throwaway12309]

Portugal has the same issue, if 70%+ of your company income is from a single entity, the company is taxed as a self employed person and not a company. So technically, the paying company doesn't have to pay nothing, but the receiving company will be responsible for those contributions. But there are ways around it and limitations, for example, in PT doesn't apply if you have employees or if the volume of business if over a certain amount or if ownership is divided by two (or more) people (if you are married, you can name your partner as a shareholder when you create the company and get around it easily)