Max Jacoby was married to Gertrud Aul, who was born on 28 March 1907. She emigrated from Berlin to Amsterdam on 1 May 1937. In 1940, Max and Gertrud lived together at Slaakstraat 5 in Amsterdam. Gertrud emigrated to New York, where her father Joseph Aul already lived, on 19 February 1940. According to an unsourced family tree reference on ancestry.com, she died on 19 August 1942 in New York.
(Sources: New York, Passenger and Crew Lists (including Castle Garden and Ellis Island), 1820-1957; Archiefkaarten Amsterdam 1939-1960, archiefnummer 30238, inventarisnummer 22)