184.108.40.206 Orphan works
If the author of a work is known but cannot be found or has been forgotten over the years and the author therefore cannot be contacted, the protection expires 70 years after their assumed date of death (Art. 29 Para. 3 CopA). But for that you must be able to assume “with a probability bordering on certainty that the author has already been dead for 70 years. […]” Such an assumption may be made if sufficient time has passed since the last signs of life from the author or may be expected due to the author’s year of birth taking into consideration the average lifespan upon expiry of the statutory deadline.” (Müller/Oertli – Reuter Gerster, Urheberrechtsgesetz, 2. edit., Art. 29 N 7a). For the calculation of the average lifespan, see also the Swiss Federal Statistic Office.