It depends on the terms of whatever contract a company signs with a clinical trial site. I suppose a company could try to build in some kind of penalties for not providing data. Each situation is going to be different.

However, a clinical trial site that is super slow is not going to get a company's business a second time, and will get a reputation for being slow. Exhibit A: IPIX is not doing the Kevetrin trial at Dana-Farber any more, even though DF wanted to continue. They were incredibly slow. So, they're out of the loop now.