Facts
C., born in 1929, ceased his professional activity on April 24, 1991 for health reasons. He was then affiliated with the "Pension Foundation for the Personnel of the P. Group" (hereinafter: the Foundation). The Foundation's regulations in force until December 31, 1991 provided that the right to a disability pension arose on the day the AI pension right opened, and that the amount of the disability pension corresponded to the retirement pension that the insured person would have received if he had remained in service until retirement age.
New Foundation regulations, which entered into force on January 1, 1992, provided for more extensive disability pension benefits, including a pension amount corresponding to 60% of the insured salary until the statutory retirement age.
The Foundation informed C. in February 1993 that he was entitled, as of April 1, 1992, to a disability pension of 13,910 francs per year, in accordance with the provisions of the regulations in force "at the time the insured risk materialized", i.e. at the beginning of his incapacity for work (April 24, 1991).
C. contested this decision and sued the Foundation for payment of a disability pension calculated according to the regulations in force on January 1, 1992. The Administrative Court of the Canton of Geneva granted his request.
The Foundation appealed against this judgment, arguing that the regulatory provisions in force in 1991, i.e. at the time of the beginning of the incapacity for work, should be applied.
Considerations
According to the case law of the Federal Court, in the event of a change in regulations, the new provisions generally apply when the factual situation giving rise to the entitlement to benefits has not yet been exhausted at the…