Who owns the intellectual property for work you do on weekends? I am an academic at a UK university and have been asked to do some consultancy work for a company who wants to own all the IP for that work. I would only do this work on the weekends.  Would my university have some claim over this IP? My university's written rules only say that the ownership of all inventions will be determined by Section 39 of the Patents Act 1977. This,  on the face of it, seems to suggest they wouldn't have any rights over the IP.

I am reluctant to ask my university until I am clear what the right answer is as their initial reaction to all enquiries is just to say no.

Section 39 Patents Act 1977


  (1)  Notwithstanding anything in any rule of law, an invention made by
  an employee shall, as between him and his employer, be taken to belong
  to his employer for the purposes of this Act and all other purposes
  if—
  
  (a)  it was made in the course of the normal duties of the employee or
  in the course of duties falling outside his normal duties, but
  specifically assigned to him, and the circumstances in either case
  were such that an invention might reasonably be expected to result
  from the carrying out of his duties; or
  
  (b)  the invention was made in the course of the duties of the employee
  and, at the time of making the invention, because of the nature of his
  duties and the particular responsibilities arising from the nature of
  his duties he had a special obligation to further the interests of the
  employer’s undertaking.
  
  (2)  Any other invention made by an employee shall, as between him and
  his employer, be taken for those purposes to belong to the employee.
  
  (3)  Where by virtue of this section an invention belongs, as
  between him and his employer, to an employee, nothing done—
  
  (a)  by or on behalf of the employee or any person claiming under him
  for the purposes of pursuing an application for a patent, or
  
  (b)  by any person for the purpose of performing or working the
  invention,
  
  shall be taken to infringe any copyright or design right to which, as
  between him and his employer, his employer is entitled in any model or
  document relating to the invention.
To broaden Bill Barth's answer a bit: you definitely need to get an lawyer involved.  You also should make certain that there is date-stamped written communication ensuring that your university's legal/IP staff are aware as well.  This may seem like a pain and may make it harder to get started on anything, but it's much better to get any possible conflicts identified and sorted out now, rather than to find yourself in the middle of a complex and lengthy lawsuit later.

I don't know about the UK, but suspect it to be similarly heterogeneous to the US, where there is an exceedingly large range of differences in the IP rights given in employment agreements at research institutions, both within academia and outside of it.  Some places are very liberal and basically claim nothing that's not "in the direct line of your duties."  Others claim even your dreams and the photos you take at your kids' birthday party (not exaggerating!).  In all cases, however, there is often a wide grey area between de jure and de facto policy, and it's important to get an agreement and understanding written down before you give IP to any second organization.