If a MODEL or DRAW DB has been created as a multiwrite database, several users can write to it simultaneously, although they cannot change the same element.

Multiwrite databases can either be Standard multiwrite databases, or Extract databases. In both types, an element must be claimed before it can be modified. Claiming an element prevents other users claiming (and modifying) the element; the element must be released before another user can change it.

Claiming can be either explicit, where you must use the CLAIM command before attempting to modify the element, or implicit, where the claim is made automatically when you try to modify the element. The claim mode is set when the DB is created. For full details see the Administrator Command Reference Manual.