The artist-dealer relationship is a bit like that of a lovers’ bond. First there is the admiration from afar; then comes the shy process of courtship, followed (if everything works out well) by a longstanding contract.

But now the art world gawps agog as the infidelity of one of its biggest stars is made public. Damien Hirst may have given a diamond skull to his dealer but, as he plans a spectacular solo sale at Sotheby’s this September, it is starting to look as if Jay Jopling may have been jilted.

True, theirs was always a fairly permissive sort of partnership. But this latest move by Hirst sets a precedent– which may not be good news for the dealer.

The dealer is not necessarily just a middleman creaming in the cash. He can play an important role in art history. Think of the connoisseur Daniel-Henry Kahnweiler, for instance, who in Paris at the beginning of the 20th century, collected and traded Cubist works. “What would have become of us if he hadn’t had business sense?” asked Picasso, who was completely unknown and all-but destitute before being discovered by Kahnweiler.

Contemporary dealers can also have a huge influence. Without Charles Saatchi, Brit Art may never have existed. But, a bit like those old millionaires who marry their secretaries, the dealer often finds he has nurtured a monster. And the relationship hits the rocks.

No one likes being dumped. Least of all artists. When Saatchi lost faith in Julian Schnabel and sold off his holdings, prices crashed quicker than the reputation of a starlet ditched by her leading man.

Dealers, too, hate to be left in the lurch. But they often are. And no wonder. They get greedy – as much as a 60 per cent cut of the sale price is not uncommon.

Discontented creatives have long been exploring alternatives. They get a bit on the side by selling straight from the studio, or they play the field, scampering from gallery to gallery. Some go it alone, hiring a shop front and putting on their own show. But, as investment capital floods into the art market, the sharks are closing in. The auction houses that once dealt with a secondary market have been steadily encroaching on the territory of the contemporary gallerist. It is Christie’s for instance, which owns and backs the many international branches of the Haunch of Venison gallery.

Now Hirst teams up with Sotheby’s and together they close in for the kill. They cut out the dealer completely.

It could turn out to be little more than the last mad coup de foudre of a dying art market. But somehow I doubt it. Hirst is proving to the art world, once again, that his talent is as much commercial as it is creative.

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