The 396 pence a share offer, through Pinault's holding company Artemis, is 26.7 per cent higher than Christie's closing share price last Friday. On 5 May, Artemis paid the same price per share for a 29 per cent stake in Christie's, owned by investor Joe Lewis.
Mr Pinault's move comes amid increasing investor interest in the art market, spurred by recent high-profile sales. The planned opening of the French art auction market to overseas auctioneers later this year is also likely to increase the number of works on sale.
"Pinault moved on Christie's at a time when the Paris market is opening up and the international art market is exploding," said Pierre Cornette de Saint-Cyr, an auctioneer at Drouot, the French state-controlled art house, which currently has a monopoly on auctions in France.
"He didn't want to be a client anymore, he wanted to be part of the machine."
The 62-year-old Mr Pinault, who started a timber company in 1963 with a family loan of $16,700, now controls more than $17bn (pounds 10.5bn) in assets, including Pinault-Printemps-Redoute, France's largest non-food retailer, and the Chateau Latour vineyard.
He is also a major shareholder in luggage maker Samsonite and the Vail Ski Resort in the US, and is a long-standing Christie's client, owning works by such artists as Andy Warhol and Pablo Picasso.
Christie's shares rose as much as 75 pence, or 24 per cent, to 388p.
Mr Pinault's bid values the whole of the company at pounds 721m. "It's absolutely fabulous for Christie's," said Cornette de Saint-Cyr.
"Pinault is the biggest art collector in France and has colossal means."
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