Corbis Corp., the stock photography agency privately owned by Bill Gates, has applied for a patent that would offer a dynamic pricing model for royalty-free images. The "royalty-free plus" (RF+) model would not offer a fixed price, as most royalty-free models do, but, instead, would offer an arrangement under which both the seller and the buyer of an image can profit.

RF+ pricing will categorize images based on intrinsic values, including the cost of obtaining the content, the source and author of the content, and the cost to manufacture the content in different media. The new pricing will also incorporate extrinsic values that pertain to a user's previous sales history, current promotions or the current popularity of the content.

RF+ will take into account the plurality of usage by different consumers and eventually may have the ability to show price changes in real time.

Corbis currently offers rights-managed and royalty-free pricing models. Competitor Getty Images offers these two pricing options as well as its "rights ready" model that allows users fixed prices in preset categories.