The deal, which was announced on 01 December, licenses Costco to sell on-demand photographs, posters and giclée canvas prints of 20,000 Corbis images at prices ranging from $1.49 to $99.99 per item. Costco customers can order the prints through the an online photo centre and collect them from one of 577 warehouse stores worldwide.

Dan Perlet, director of communications at Corbis, tells BJP that he was "surprised" at the level of concern he has encountered among contributors.

But, some photographers are worried that customers may scan images they have bought from Costco for resale, not understanding the copyright limitations of their purchases. Perlet has moved to reassure them, saying that "the likelihood of this is very low. Online piracy is much bigger of a threat than the work it takes for someone to scan an image." He adds that since "you can find many of these images already on Google" the risk of copyright infringement is "not a new threat."

But Perlet says that Corbis will be "using technology such as Picscout as well as word of mouth" to monitor for any online infringement of the images.

As part of the deal, photographers will be paid royalties retrospectively per unit of merchandise sold, a provision Perlet describes as "significantly more advantageous" than the upfront fee provided in other Corbis merchandising agreements.

But, he stresses, "this is not a new type of agreement. It is part of the standard Corbis contract that the vast majority of contributors have signed."

As a result, current contributors cannot opt out of the clause. However, photographers in the process of signing a new contract with Corbis will have the opportunity to negotiate the terms.

When asked whether the deal could undervalue photographers' work, Perlet says that its relationship with Costco "will not impact fine art limited edition prints and is nothing new for poster or merchandise work."

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