Other entrepreneurs "doing the double" recently include David Krantz of Racing Green, Roger Myers and Robert Earl of Pelican, and Michael Cannon of Magic Pub, to name a few.
Some critics see this as evidence of a "British disease", comparing it unfavourably with German entrepreneurs who prefer to keep their companies private and grow them organically.
Others say that the latest raft of cash-outs is spurred by fears of a Labour government and the more onerous taxes and regulations it may introduce, as well as a possible fall in the stock market in the run-up to the general election. "I believe these factors are driving people to sell earlier than they otherwise would have done," said Nigel Pantling, head of corporate finance at Hambros.
The flow of "second-time-around" deals is undeniable. For instance Pet City's Mr Clarke made his first fortune by selling his Majestic Warehouse business in 1989 for pounds 15m, while his colleague, Mr Northcott, sold what was to become the B&Q DIY chain to Kingfisher in 1981 for pounds 20m.
Another retail entrepreneur to do well this week was Mr Krantz, 43, who netted his second high street fortune when he sold the Racing Green mail order and stores group to Burton for pounds 19m.
He also founded the Blazer menswear chain in the early 1980s before selling it to Storehouse for pounds 5m in 1987. It was bought by Moss Bros in June.
Pubs and restaurants have provided rich pickings for entrepreneurs. Mr Myers and Karen Jones built up the Pelican restaurant chain in six frenetic years from nothing to more than 100 outlets and sold it to Whitbread earlier this year for pounds 133m. Some pounds 100m of that was goodwill; the rewards for Mr Myers, chairman, were generous - around pounds 2.8m.
The couple opened their first Pelican outlet, Cafe Rouge in Richmond, Surrey, with the proceeds of selling on their previous venture. Theme Holdings, a restaurant and leisure group, traded briefly on the third market in the mid-1980s before being snapped up for pounds 17m in 1987.
Another who has done the double is Mr Cannon, who in June made a fortune for the second time in three years by selling his Magic Pub chain to Greene King for nearly pounds 200m.
Trevor Hemmings, who retired earlier this year as a director of Scottish & Newcastle Breweries, has made a habit of collecting fortunes. He is best known as the Fred Pontin protege who made a fortune buying the holiday camp business from Bass, and selling it on soon after to Scottish & Newcastle for shares worth more than pounds 100m.