Are you a tax attorney?:-)

We did not know nor care how they handle their expenses. All we need to do is to make sure that we are not doing any trials for them while accepting their hospitality.

Many hospital, mostly large ones, conduct a large number of clinical trials. Most, if not all, hospitals are non-profit organizations. How do you suppose these company doing trials recruit patients? Through hospitals, of course. Pharmaceutical pay money for these trial. It is a multiple-partner business. To make it more complicated, there are players oversee these trials to meet FDA standard. And last and the most important, the FDA.