Corbis has agreed to buy The Stock Market (TSM), a privately-owned stock photography agency.

Corbis announced the acquisition, which is expected to be completed in mid-April, yesterday.

The Stock Market began supplying stock photography to the creative industry in 1981, and now claims to be the biggest independent agency in the world, with more than 3 million images. It also claims to be the first to launch a full e-commerce solution for buying traditionally licensed images.

Corbis has 900 employees in its offices in Seattle, London, New York, Los Angeles and Paris, and stocks 65 million images – 2.1 million online.