Third-party liability for social security contributions arises only upon the tax authority's decision, not automatically upon asset acquisition.

The Supreme Court dismissed the cassation appeal filed by three companies against a social security fund decision. The companies argued that their liability for social security contributions should be determined by the tax law provisions valid at the time they acquired the assets, rather than the law at the time of the decision. The court ruled that the liability of a third party is constituted solely by the tax authority's decision, which must be evaluated based on the legal provisions in force at the moment of that decision's issuance and delivery.