Information from one object A can only flow to another object B iff B is at least as tainted as A in every category. This is the flow to relationship. A restriction imposed by a particular category can be bypassed by objects that own that category. Ownership of a category is specified as an additional degree . Categories are only created by threads. A thread that creates a new category is the only owner of that category and can then grant ownership to another thread or to a gate (another kernel object).