South African-based Famous Brands said it saw ‘substantial growth potential’ for the 75-strong chain in the UK and was aiming to open 10-15 restaurants a year.
GBK’s current team will continue to manage the business and the sale will have no impact on its current operations.
Kevin Hedderwick, Famous Brands’ group strategic advisor, said the deal was largest in the group’s history and an opportunity for it to enter the premium market.
“Quite simply, GBK is a best in class business and brand, with growing consumer equity, supported by a phenomenal leadership team,” he said.
“GBK has an impressive historical financial track record and delivered in the context of an economic downturn.”
He added that there was interest in expanding the chain in Ireland and opening stores in Famous Brand’s native South Africa.
Alastair Murdoch, CEO of GBK, said: “Our aims remain the same: to continue opening 10-15 restaurants a year in the UK, continually elevate our food, and look at other growth opportunities.”
GBK was founded in Battersea, London in 2001 by three New Zealanders with the backing of Kiwi chef Peter Gordon.
It was acquired by the Yellowwoods Group in 2010 leading to rapid growth of the chain - 93 per cent of its restaurant portfolio has either opened or been refurbished in the last five years.