Grant Shapps, the Conservative party chairman, posed as a "multimillion-dollar web marketer" named Michael Green who spoke to reveal the secrets of his trade at a $3,000-a-head internet conference in Las Vegas while he was the Tory party candidate for Welwyn Hatfield.

The pictorial evidence of his double life, revealed online by a fellow conference speaker, will pile pressure on Shapps to explain his links to a network of websites which have been blocked by Google for breaching its rules on copyright infringement and encouraging customers to plagiarise content.

But at the age of 35, Shapps claimed already to have established "the world's largest internet marketing forum". A few years later while a member of the shadow cabinet, he also had time to run phone lines where for $297 an hour Green would give tips to aspiring entrepreneurs.

Casting himself as an internet marketing guru with products and coaching services guaranteed to generate income, Shapps owned and ran until 2008 a series of websites making claims that still dog him despite attempts to downplay his personal role. Using the website MichaelGreenConsulting.com, which operated from 2004 until it was removed from the internet in 2009, Shapps claimed to run the "world's largest internet marketing forum" with his company How To Corp.

While serving the constituents of Welwyn Hatfield, shadowing the housing brief and taking charge of Tory byelection campaigns, Shapps also ran phone lines offering expert advice on internet marketing. "The fee for my one-hour phone consultation is $297 (US). I make the call to you, no matter where you are in the world," the website read. In 2004 Shapps, then the Tory candidate for the Hertfordshire seat, was passing himself off as Green and began to appear at web marketing conferences – speaking at a $2,797-a-ticket convention in Las Vegas's New York New York Hotel and Casino, whose facade is a lifesize replica of 12 Manhattan skyscrapers including a 529-foot-tall copy of the Empire State building. It was here that Shapps was pictured as Green.

After winning the seat in 2005 Shapps registered his shareholding in How To Corp on the parliamentary register of interests. He has never revealed the amount paid out to him from the company in dividends. Shapps founded How To Corp in 2000, focusing on internet marketing, but rarely touched upon it in interviews – a mention of Green was removed from his Wikipedia entry.

In 2008 Shapps transferred his share in How To Corp to his wife, Belinda, a Conservative activist who had failed to win a council seat for the Tories in Camden, north London, a decade earlier. The Tory chairman says he "no longer has any involvement" in the company. The site is now fronted by a Sebastian Fox.

In 2010 the family firm launched Traffic Paymaster – software that inflates a website's advertising revenue by copying and retouching other people's content, which Labour has called on police to investigate for possible fraud and copyright violations. Last week, after the Guardian reported Labour's call, Traffic Paymaster disappeared from the web.

The Guardian has now established that Traffic Paymaster "scrapes and spins" content from at least four websites: ezinearticles.com, goarticles.com, ehow.com and ezinemark.com. These sites appear to prohibit the "plagiarising of information".

"Use of site scrapers, article crawlers, or other automated methods/scripts to mine the article content of GoArticles are expressly forbidden unless permission has been specifically granted by GoArticles.com," reads one warning.

Although registered to an office in Pinner, north-west London, How To Corp products and services are priced in US dollars, and in its marketing materials How To Corp claims to have an office in the United States and lists US phone and fax numbers. Shapps had claimed this was necessary since 90% of the site's revenue came from the US. The company lists offices in Pennsylvania. However the Pennsylvanian department of state said it had no record of the company. The addresses given were traced to residential properties. "If a company had been trading from Pennsylvania then it would have to be registered here. Otherwise there are fines of $500," said the state authorities.

A Conservative spokesman said that Shapps's "involvement in business has always been entirely properly declared with the parliamentary authorities and subsequently ministerial authorities", including being cleared by Sir Bob Kerslake, the head of the civil service.

The spokesman continued: "Grant had a career in business before entering politics. He is completely open about this and believes that parliament benefits from the experience of members from a wide variety of backgrounds. His involvement in business has always been entirely and properly declared with the relevant authorities, confirmation of which includes a letter from the head of the home civil service, Bob Kerslake. It is completely incorrect to suggest otherwise."

Labour said it would be pressing Shapps to explain his past. Steve McCabe, the Labour MP who has called on the Crown Prosecution Service to investigate How To Corp, said: "Grant Shapps's multiple personalities and questionable business practices are becoming a major embarrassment to the Conservative Party.

"It is little wonder the Tory-led government can't start to deal with the myriad problems, from a recession made in Downing Street to the debacle of the GCSE results, with Grant Shapps overseeing proceedings. He must make a full statement on his past and why he found it necessary to use an alias to conduct business."