It is worth while to note that RUP and the UP, although very similar in nature, are two different things. The UP is an open standard from the authors of the UML, made available through OMG (The Object Management Group). The RUP, on the other hand, is a commercial version of the UP made offered from IBM, which acquired Rational Corp in 2003. It supplies all the standards, templates, tools and other necessities that are not included in the UP, things that make the implementation of the UP in your project much easier. In Object Oriented terms, RUP is a subclass of UP, that both extends and overrides the features and artifacts found in UP.