This is sort of true, sort of not. The primary investigator who registers a clinical trial is obligated to report the results back to the registry. But if they

This is sort of true, sort of not. The primary investigator who registers a clinical trial is obligated to report the results back to the registry. But if they get a negative result, they are still going to have a hard time finding a decent scientific journal that's willing to publish it. And an unpublished result isn't going to have nearly the visibility that a published result does.