From the charter:
The provenance of information is crucial to making determinations about whether information is trusted, how to integrate diverse information sources, and how to give credit to originators when reusing information. Broadly construed, provenance encompasses the initial sources of information used as well as any entity and process involved in producing a result. In an open and inclusive environment such as the Web, users find information that is often contradictory or questionable. People make trust judgements based on provenance that may or may not be explicitly offered to them. Reasoners in the Semantic Web will need explicit representations of provenance information in order to make trust judgements about the information they use. With the arrival of massive amounts of Semantic Web data (eg, via the Linked Open Data community) information about the origin of that data, ie, provenance, becomes an important factor in developing new Semantic Web applications. Therefore, a crucial enabler of the Semantic Web deployment is the explicit representation of provenance information that is accessible to machines, not just to humans.