Mercury Interactive, the software maker bought by Hewlett-Packard for $4.5bn last year, has agreed to pay $117.5m to settle a classaction lawsuit over options backdating - the biggest civil settlement in an options backdating case, according to plaintiffs' attorneys.

Mercury was one of the first companies to run into trouble over options backdating, a potentially fraudulent practice in which the grant dates of stock options are changed after the fact to coincide with low points in the value of a company's shares.