Leon Soubice was a son of Salomon Soubice and Marianne Pach. He married in Amsterdam Watergraafsmeer on 22 December 1932 to Naatje van Kollem, daughter of Levie van Kollem and Jetje Duijts. Genlias.
In addition, a Jokos file (number 55446) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.The Jokos file reveals that a claim was lodged for compensation for valuables surrendered to the Lippmann-Rosenthal looting bank (L-claim, number 11205/8417).