In June 1902, Einstein received the letter he had been impatiently waiting for: a positive answer regarding his application to be a technical expert – class III at the Federal Office for Intellectual Property in Bern, colloquially known as the patent office.

The job at the Federal Office for Intellectual Property – Einstein referred to it tongue-in-cheek as his "cobbler's trade" – turned out to be stroke of good fortune because it was excellently paid (CHF 3500 per year) and was undemanding for his nimble intelligence. He spoke of the Federal Office for Intellectual Property as "that worldly cloister where I hatched my most beautiful ideas". With his courteousness and modesty and his humorous approach to life, Einstein was very well liked. On 1 April 1906, he was promoted to technical expert – class II. He managed his time exactly: eight hours of work, eight hours of «allotria» (miscellaneous) and scientific work, and eight hours of sleep (which he often used instead for writing his manuscripts). Much to the Federal Office for Intellectual Property's regret, he left in the autumn of 1909 to take over the chair in theoretical physics at the University of Zurich.