Four U.S. journalists have filed a lawsuit against Hewlett-Packard (HP), claiming they suffered a “serious invasion of privacy,” when private investigators hired by HP assumed false identities to acquire their personal phone records.

Reporters from the Associated Press and the technology Web site CNET are among a dozen people targeted in an investigation ordered by HP's former chairwoman, Patricia Dunn, into who was leaking boardroom information. Dunn lost her job due to the incident, and California's attorney general brought charges against HP, which the company settled for $14.5 million. Charges against Dunn were dismissed in March.

The journalists' lawyers have said that HP's spying hindered their ability to do their jobs, calling the company's actions “illegal, reprehensible conduct,” according to an article by Media Guardian.

The company's spying was made public last Septmber, when Thomas Perkins, then HP's director, resigned and went public with concerns over the route the company had taken in trying to learn the source of negative stories.

“It emerged that investigators had staked out rubbish bins outside journalists' homes, tracked one reporter on a trip to Disneyland and had even discussed posing as cleaners to infiltrate the offices of news organisations,” according to a Media Guardian article.