A person (or corporate entity) only becomes a shareholder when they receive shares that are issued by the Company that they are investing in. The issue of a SAFE to an individual or corporate entity is not the same as the issue of shares. A SAFE is an agreement made with an investor where they provide funding, in return for shares in your startup in the future, to be issued at your next funding round or as set out in the terms of your SAFE note. A SAFE holder only becomes a shareholder when those shares are issued in the future and they are entered onto the register of members.