When you are a token-holder in a syndicate, you have a special right to buy tokens before everyone else. In legal terms, this is called “pre-emption right”, but what it means is that certain people have a priority right to buy something before anyone else, at a given price.
If no one uses their priority right, anyone else can access and buy the tokens.
The underlying reasons of priority right are several: (i) to allow existing token-holders to keep their investment in the start-up company closed and thus limit the number of token-holders within the syndicate, and/or (ii) to use the possibility to increase their share in the syndicate. For instance, if an existing token-holder decides to sell their tokens, the other investors in the syndicate have the right to step in and buy the tokens at the agreed price.