In a patent infringement case I was "involved" in many years ago, validity of a patent covering one very commercial composition was in issue. Evidence bearing on the commercial success of that compound in the market place was in issue--evidence of commercial success(particularly unexpected commercial success)--was treated as evidence of the non-obviousness of the composition under 35 U.S.C. 103.
I saw 2 experts testify, one testifying on behalf of plaintiff owning the patent, the other testifying on behalf of the entity accused of infringing the patent. The relative accuracy of data from IMS, Symphony, and even Opera was the subject of testimony from both that occupied much of the day, with both experts ultimately forced to agree that the source of the data base each was arguing was more relevant was not necessarily complete itself.