MacDonald Dettwiler & Associates (MDA), the company at the heart of the National Land Information Service (NLIS), is facing an Office of Fair Trading probe into claims that it is trying to monopolise e-conveyancing.

MDA, which fronts a consortium that includes the Law Society, has the contract to run the NLIS hub, the gateway to electronic property information, and is also one of the three channel licensees, through which solicitors buy the information.

Fellow licensee TM Property Service has complained that MDA's dual role allows it 'to cross-subsidise its NLIS operations in order to capture market share' and so threaten the other channels' viability

In a statement, MDA said it had filed its defence.

'There is no merit to these claims,' it said.

A Law Society spokesman said NLIS and all its channels provide a good service.

'We await the outcome of the OFT's investigation.'