Hugh Osmond, founder of Punch Taverns, has bought up a two per cent stake in Belgo, the beer and chips chain run by Luke Johnson.
Matthew Allen, a director of Pizza Express and one of the founders of Punch has also been buying shares.
Mr Osmond and Mr Johnson are former business partners. They ran nightclubs together straight from university and were responsible for the national roll-out of Pizza Express.
The relationship soured in March when Mr Osmond forced Mr Johnson to withdraw from the running for the 3,000 pubs put up for sale by Whitbread. He invoked a non-compete clause signed by Mr Johnson as a shareholder in Punch Taverns in 1999. The Laurel Pub Company, the Morgan Grenfell takeover vehicle, eventually took the estate.
Some will interpret Mr Osmond's move as an esculation of the growing rivalry but he insisted his interest in Belgo was as an investor. He was reported to have said: "We thought Luke Johnson could make us some money."
The identity of Kintaro International, the mystery investor that bought up 14 per cent of the company, remains unknown.
It has been a fairly miserable year for Belgo, which with the rest of the industry, has had to absorb foot-and-mouth, economic slowdown and the fall-out of the September 11 attacks in America.
Belgo, which also owns the celebrated London eateries Le Caprice and The Ivy, recently announced it will switch its focus from the Beirodrome outlets to its Strada pizza chain. It will also change its name to Signature Restaurants.
Related stories:
Is Johnson the mystery Belgo investor? (17 October 2001)
Mystery investor 'Kintoro' stalks Belgo (08 October 2001)
New name for Belgo in shift towards restaurant business (26 September 2001)
Whitbread shortlist drawn up (19 March 2001)