Since the pair acquired the four venues between 2007 and 2011, Nando's has been trying to force the franchisors into making significant investment into the businesses. It is this the dispute centres on.

Nando's says the franchisees haven't upgraded the restaurants since they bought them, in some cases as long as nine years ago.

 "As a consequence, the fit-out and branding used in all four restaurants are out of date and not in line with Nando's current standards," business development manager Scott Hamilton says in an affidavit tendered to court as part of the case.

The company wants the franchisees to spend almost A$1.2m to refurbish the Narre Warren, Wareca and Braeside businesses, the documents indicate.

The case has become a key test in head office's ability to force franchisees to invest in their business, Hamilton's affidavit says.

"A number of franchisees in the Victorian market have already raised the pending litigation... as a reason to delay their own refurbishment works".

 Franchisees have a requirement to upgrade and invest in stores when head office "reasonably requires" them to do so written into their franchise agreement, a counterclaim filed by the company says.