The act of clearing houses and brokerages selecting short option and future contract holders to deliver underlying securities or commodities of maturing or exercised/tendered contracts.
Not all contracts will typically be exercised or tendered; those that are need to be settled with delivery of the underlying security/commodity. Most often, clearing houses will randomly allocate assigned contracts to brokerages that, in turn, randomly select which of their clients will be assigned.


Assign
The act of clearing houses and brokerages selecting short option and future contract holders to deliver underlying securities or commodities of maturing or exercised/tendered contracts.
Not all contracts will typically be exercised or tendered; those that are need to be settled with delivery of the underlying security/commodity. Most often, clearing houses will randomly allocate assigned contracts to brokerages that, in turn, randomly select which of their clients will be assigned.