THEY are leading figures in Scotland's hospitality industry with a bitter rivalry stretching back decades.
But an unusual legal move has resulted in the dirty linen of two major stables of bars and clubs being made public, revealing a petty squabble which has gone all the way to the highest civil court in the land.
G1 Group, owned by leisure entrepreneur Stefan King, has been given the go-ahead by the Court of Session to try to overturn a ruling secured by the firm owned by the family of adversary James Mortimer over the issue of outside seating at a Glasgow venue.
In a blow to his competitor, Lord Malcolm has upheld an appeal by Mr King, promising further legal wranglings and rancour between the pair.
Both G1 and the Mortimer family's Lynnet Leisure own neighbouring high-profile outlets on Glasgow's Royal Exchange Square, where even the location of their bins has led to niggles and complaints to the local authority.
The Mortimer family own swathes of the square, including Club 29 and the famous Rogano restaurant, with plans to build a hotel to the rear of their properties, while Mr King has The Social.
With little love lost between the pair, it is understood Lynnet Leisure has in the past even offered, unsuccessfully, to buy The Social from G1.
Matters came to a head three years ago with complaints that The Social's outside seating was infringing on access to Club 29, leading to Glenerrol, a Lynnet spin-off, and other property owners in the block drawing up a regulation limiting use of the "front common property".
An error by G1 in appealing the regulation under the Arbitration (Scotland) Act 2010 led to it being thrown out and Mr King then taking the case to the Outer House of the Court of Session.
But in doing so, as well as costing G1 an estimated £40,000-plus, it has made a largely anonymous legal process public, revealing the extent to which minor disputes between the pair have escalated.
Craig Connal, QC, a partner with leading law firm Pinsent Masons said: "One of the advantages of sorting your disputes at arbitration, common in the property world, is that dirty linen is aired behind closed doors. The process is private. So cases which emerge in public are rare as hens' teeth. Even those that do hit the courts are often anonymous. So G1 against Glenerrol is a very rare beast."
The Arbitrator, who is Dean of the Royal Faculty of Procurators in Glasgow, ruled against G1 on the basis its legal challenge was not correctly attributed to the part of the company empire making the challenge.
However, Lord Malcolm ruled that too technical an interpretation had been adopted by the Arbitrator and sent it back for reconsideration, while having a polite pop at the length of time the process had taken to this stage.
The ruling puts the case back to square one, where whatever outcome will leave either Mr King or Mr Mortimer deeply unhappy.
One source said: "It has been going on for years between this pair. They even complain about each other's bins or believe the other gets preferential treatment at their expense.
"This is all in an avenue of the law which is very tricky, hung up on technical points and can get bogged down. It's most likely cost and difficulty in this aspect of the case were secondary to proving points and not taking your rival getting one-up on you lying down."
Mr Mortimer is often credited with helping propel Glasgow to the UK's nightspots A-list, bringing a touch of glamour to venues in the late 1980s and early 1990s, with Lynnet Leisure also owning venues in Paisley and Hamilton. He counts Sir Alex Ferguson among close friends.
Stefan King's G1 Group was the new kid on the block in the 1990s and owns dozens of venues across Scotland. The firm has been at the centre of recent controversies, including a two-way mirror in the ladies' toilets of its Shimmy Club.
No-one from either G1 or Lynnet Leisure was available for comment.