MHRA notification

When do you need to notify the MHRA for a clinical trial involving a medical device prototype? I think I am right in saying that any work with patients would need ethics approval locally, but you do not need to notify the MHRA if the prototype is developed in-house and won’t be sold. However, there are a number of scenarios I wanted to ask about:

  1. If the prototype is developed in a university lab and will be tested in an associated hospital?
  2. If the prototype is developed by a university and tested in a hospital where there is no affiliation?
  3. If a later-stage prototype is designed and built by a third party company and will be tested in a hospital, but the data will not be used for regulatory submission?
  4. If a later-stage prototype is designed and built by a third party company and will be tested in a hospital, but the data will be used for regulatory submission?

I hope someone can help with the above. I may be wrong in my assumptions depending on the device class