The former Harvard classmates are now both building companies in Palo Alto. Mr Greenspan's software venture, Think Computer, has not caught on quite like Mr Zuckerberg's Facebook, which boasts 70 million users worldwide. -- PHOTO: AP

In a petition filedon Tuesday with the US Patent and Trademark Office, Mr Aaron Greenspan is seeking to cancel Facebook's legal claim to its name.

Mr Greenspan, 25, argues Mr Zuckerberg, 23, had no right to trademark the Facebook name in 2005 because the term had been used generically for decades at Harvard University, where they first met.

What is more, Mr Greenspan maintains he used the term 'Face Book' as part of an online service called houseSYSTEM a few months before Mr Zuckerberg unveiled his now-famous Web site in 2004.

The former Harvard classmates are now both building companies in Palo Alto with differing degrees of success. Mr Greenspan's software venture, Think Computer, has not caught on quite like Mr Zuckerberg's Facebook, which boasts 70 million users worldwide.

This is not the first time legal questions have been raised about whether Mr Zuckerberg came up with the idea that blossomed into one of the Internet's hottest companies and made him a billionaire in the process.

A trio of former Harvard students have been fighting over Facebook's origin since 2004, alleging in a federal lawsuit that Mr Zuckerberg stole the social networking concept after they hired him to work on a Web site that eventually became ConnectU.

Facebook reportedly is nearing a settlement with ConnectU founders, twin brothers Cameron and Tyler Winklevoss and their partner, Divya Narendra. The New York Times reported the confidential settlement talks earlier this month.

Long before Mr Zuckerberg moved to Silicon Valley in 2004, the Facebook term was widely used at Harvard to describe any paper or electronic book that displayed the faces of students and faculty 'in a structured manner,' Mr Greenspan wrote in his petition.

Picking up on that theme, Mr Greenspan said houseSYSTEM introduced a student locator called 'the Face Book' in September 2003 - at least four months before Zuckerberg unveiled 'thefacebook.com.'

Mr Greenspan said he has documentation, including e-mail exchanges, to show Mr Zuckerberg knew about Mr Greenspan's Face Book feature and even considered melding it into the thefacebook.com.

A Facebook representative declined to comment on Mr Greenspan's petition. Mr Greenspan said he hasn't talked to Mr Zuckerberg since 2006.

Mr Greenspan acknowledged he might be willing to drop his petition for the right amount of money. But he said what he really wants is the legal right to use the term Facebook in the title of a 335-page 'memoir' that he plans to self-publish later this month.

He intends to call the book, 'Authoritas: One Student's Harvard admissions and the founding of the Facebook era.'

But websites would not let Mr Greenspan advertise the book under that title because of Facebook's trademark, prompting him to fight for the rights to the name. -- AP