Facts
In 1971, [Z.] carried out gardening work for the terrace of the apartment of the spouses X. in Zurich-Wollishofen. In 1977, [Z.] was operated on by Mrs. X., a physician and owner of the apartment. In December 1980, they concluded a settlement before the District Court of Horgen concerning this medical bill and the balance of Z.'s wage claim. On 26 February 1981, Mrs. X. asked [Z.] to waive the statute of limitations for two years in order to avoid enforcement proceedings to interrupt it, which he did not do. [Z.] was then subjected to enforcement proceedings for 500,000 francs, to which he filed an objection. In October 1981, [Z.] filed an action for a declaratory judgment to have it declared that he did not owe the amount of 500,000 francs pursued and that the enforcement proceedings had unduly prejudiced his personal situation. The District Court of Zurich dismissed the claim. The High Court of the Canton of Zurich confirmed this dismissal for the second and third heads of claim, but upheld the first head.Considerations
The Federal Tribunal considers that the admissibility of an action for a declaratory judgment is determined exclusively by the applicable substantive law. When it comes to claims based on federal private law, federal law alone determines the conditions for the admissibility of such an action. The Federal Tribunal abandons its previous case law which accepted that the cantons could provide for other declaratory actions than those arising from federal law. A negative…