For assuming the position, you have to meet the requirements (PhD) specified in the job posting. The Freie Universität Berlin recognizes the day of your successful thesis defense as your graduation. If you haven’t completed the degree by the time of application, please enclose a document that assures that you will able to finish the PhD by the time the position starts. Ideally, the scheduled date for your thesis defense should be mentioned in this document. By the date that your employment officially starts, an official notice of completion (most commonly the preliminary PhD certificate) has to be submitted.