The claim changes creditor, but does the obligation change? Assignment of claims, ancillary rights and the debtor's defences
The assignment of claims is a central institution of the law of obligations and of contractual practice. It allows a creditor to transfer his claim to a third party, with its security and ancillary rights, without the need to create a new obligation. The “Código Civil” —the Spanish Civil Code, CC—, from articles 1526 onwards, and the “Ley Hipotecaria”, Spain's Mortgage Act, in its provisions on the assignment of mortgage-secured claims, provide the basic framework for analysing what is transferred with the claim, what part is played by the debtor's consent and by notice to him, what effects payment to the assignor has, what defences the debtor may raise against the assignee and how set-off operates. STS 22/2026 of 14 January, a judgment of the “Tribunal Supremo”, Spain's Supreme Court, returns to an essential principle: assignment does not create a new obligation, the assignee acquires the same claim, with its identity and content, and the change of creditor is not equivalent to the birth of a different claim. That principle makes it possible to build a broad body of doctrine on the identity of the obligation, the debtor's position and the difference between assignment, subrogation and novation.