For any graduating artist, to have just one painting bought by Charles Saatchi is the stuff of dreams.

But three students from the Royal Academy Schools were astonished yesterday when the man who made the fortunes of Damien Hirst, Tracey Emin and the Chapman brothers picked their entire graduation show.

Hours before the public was allowed in to to see the exhibition the walls came out in a rash of bright red dots.

Mr Saatchi, 65, snapped up five cutout cartoon characters by Angus Sanders-Dunnachie, 28, the total price of which was £7,900; seven of ten landscapes by Jill Mason, 33, each priced at up to £600; and all 13 paintings by Carla Busuttil, 26, which were priced between £450 and £2,500.

They were exhibiting works with 14 other students who had completed the RA Schools’ postgraduate course Mr Saatchi had asked for a discount, but none of the students wanted to reveal how much they had agreed to. Their excitement suggested that they would have given away their work to the collector, such is his influence, and anyone now wanting to buy their works can expect to pay far more than he did.

Mr Saatchi, 65, who made his multi-million-pound fortune in advertising, is seen as a barometer of the art market, with his purchases setting trends and making headlines. In 1997 two works he championed – the Chapman brothers’ mutant mannequins with genitalia for facial features and Hirst’s rotting cow head – created a furore when they appeared at the Royal Academy’s Sensation show.

More recently, his purchases of contemporary American and Chinese artists have inspired interest.

While Mr Saatchi likes to buy in bulk, allowing him to control an artist’s market, he also likes to sell in bulk, which unnerves the market and led to critics dismissing him as a glorified dealer.

In 2003 he sold almost all his Hirsts back to the artist and his dealer. Relations between the artist and patron had soured after Hirst described Mr Saatchi as a “childish” businessman who “only recognises art with his wallet”. But both made a considerable profit from the deal.

Professor Maurice Cockrill, Keeper of the Royal Academy, told The Times that Mr Saatchi had the Midas touch when it came to art.

“His buying immediately puts values up. If it’s just a sale to Joe Bloggs, saying you have got a work in Joe Bloggs’s collection, it doesn’t carry much weight,” he said.

“Charles Saatchi’s purchase makes others think that if [an artist] has drawn his attention, there must be some future in that artist. He associates with winners. Losers are not in his sights.”

Professor Cockrill had hovered in the background while Mr Saatchi wandered around the show. “He likes to be left alone,” he said. “I didn’t do any prompting.” From time to time, Mr Saatchi would ask him a question. He wanted to know, for example, whether Ms Busuttil was a “boy or girl” and he was particularly interested that her portraits were of modern-day political figures, including Baroness Thatcher, for whom Mr Saatchi and his brother, Maurice, coined the “Labour Isn’t Working” slogan in the Conservatives’ victorious general election campaign in 1979.

The figures in Ms Busuttil’s paintings do not have any facial features (she did not take the RA Schools’ optional life-drawing classes). Instead, she sought to create caricatures, hinting at Lady Thatcher’s identity with a pearl necklace and shoulder-pads, she said.

While Mr Saatchi said that the RA Schools had staged “easily the outstanding degree show of any art school so far this year”, Edna Weiss, a painter and a student there from 1946 to 1951, was less than impressed by the offerings.

Having always believed that the Royal Academy – the training ground of Turner and Constable – was supposed to be the centre of excellence in craftsmanship, she said: “Why do these students need an art school? Who’s teaching them to do these things? I have no idea why Saatchi would want them.”

Another visitor to the show said of Ms Busuttil’s paintings: “Looks like a collection of blobs and smiley faces.”

The RA Schools Show 2008 is open to the public until June 20.

The Midas touch Damien Hirst

Name was made after Charles Saatchi bought most of his works. Prices have soared to extraordinary heights. Last year he was crowned, briefly, the world’s most-expensive living artist, after a medicine chest – which could be mistaken for just that if placed anywhere other than an auction house or art gallery – sold for £9.65 million at Sotheby’s in London

Jenny Saville

Sold her entire degree show to him in 1992. Her work has sold subsequently for seven-figure sums

Tracey Emin

Mr Saatchi is said to have bought My Bed, which featured soiled sheets, for £150,000. Within six years, it was valued at £1 million

Natasha Kissell

Saatchi bought two of her huge landscape paintings at her degree show in 2003. This kick-started interest and her prices soared way beyond the “student rate” that he paid

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