In the latest battle in a rivalry stretching back decades, Stefan King - owner of G1 Group, which owns venues such the Corinthian - secured a victory over the family of James Mortimer in a row over outdoor seating at Glasgow's Royal Exchange Square pedestrian precinct.
The seemingly petty squabble has resulted in a judgment being issued by an arbiter that clarifies the position on who has control over pavements and pedestrian areas throughout Scotland.
It means that even if building proprietors own the area outside their property, if it is a public pathway or road it is controlled by the council, which determines what is allowed to operate there.
A source close to the case said: "It's a landmark case because it's the first to clarify the position on this.
"It's often assumed that if you own a building then you normally own the bit out the front too, but when the pavement is controlled by the council's roads department, the owners of the building don't have any rights.
"They have to apply for a licence to operate outdoors, and if that is granted the owners and occupiers have no say in it."
The row between Mr King and the Mortimers was sparked three years ago when the family - who own several buildings in the square including private members' club 29 - tried to force Mr King to remove an outdoor seating area at G1 Group's The Social, a bar beneath 29.
The Mortimers, whose firm Gleneroll owns 29, claim the outdoor cafe is an eyesore that infringes on access to the bar and has attracted complaints from their customers.
They drew up a regulation with other property owners in the square trying to have the seating area removed under common property laws.
However, the arbiter ruled the owners have no say as it is under the control of Glasgow City Council's roads department.
As Mr King has a licence from the council allowing him to operate the outdoor area, there is no basis for him to remove it.
The source said: "The whole point was that Mortimer's 29 is stuck in the corner of the square and he wanted these tables and chairs to be taken away so he could have a better frontage for 29.
"He thought he could impose a regulation stopping King operating the street cafe but the arbiter has confirmed that is not the case. The regulation he drew up is null and void because the pavement is under the control of the council."
The case has been heard at the Court of Session in Edinburgh as well as going through the arbitration process at the Royal Faculty of Procurators in Glasgow.
Mr Mortimer is now liable for expenses in both hearings, which are estimated to run to a six-figure sum.
A Glenerrol spokesman claimed the firm tried to negotiate with G1 prior to drawing up the regulation, asking for the removal of just three sets of tables, but received no response.
He added: "We strived to find a reasonable compromise with G1, at one point asking them to remove just three long tables from their current holding of 40 tables over two spaces in the Square.
"The outside furniture of The Social is an eyesore in one of the city's most beautiful areas; it dominates the walkway, forcing passers-by to squeeze past, which we know our customers find awkward and intimidating.
"The furniture is there constantly, 364 days of the year, even in rain or snow when it's almost always deserted. Royal Exchange Square is too important to be used as a storage facility.
"We own over 80% of the building and we care about the long-term good of this historic area." "We are at a loss to understand the rationale behind both this decision and the inability to reach a compromise with the G1 Group.
"We are now considering our options"
G1 Group was unavailable for comment.