1. A computer-implemented method comprising: receiving, at a document broker, a plurality of documents; creating a main topic tree of filtering elements in the document broker; parsing out a sub-tree from the main topic tree, wherein the sub-tree describes an authorization filter for a document supplied to the document broker and requested by a subscriber, and wherein the sub-tree is in an optimized format that is executable for filtering access to the document for the subscriber; storing the sub-tree with the document broker under an alias name as an alias-named filter, wherein the alias-named filter is automatically permanently stored with the document broker after the subscriber causes a temporary storing of the sub-tree as the alias-named filter a pre-determined number of times; and in response to a request from the subscriber for the alias-named filter, supplying the alias-named filter to the document broker to determine if the document is authorized to be supplied to the subscriber.