The Pirate Party, now two weeks old, has 259 fully paid-up members.
The organisation was registered as an official political party on 11 August by the Electoral Commission and has three core policies: the reform of copyright and patent law; the end of excessive surveillance by government and business; and to ensure freedom of speech.
Reports from various quarters last week suggested that around 100 new members are signing up every hour to the party, but Eric Priezkalns, party treasurer, said then he still needed to validate the figures about memberships received to date.
The validation has now come as the party posted a blog post on Saturday outlining its membership gains in recent weeks and that in just the last few days of last week, the party's web site was visited 25,000 times.
The party's blog post said, "By the end of today we will have more members than the Libertarian Party, who formed in November 2007 and describe their growth as 'steady'. If we keep this up, then by the middle of next week we will have more members than George Galloway's Respect Coalition. By early November, we would be on a par with the Green Party. By the end of November, we would have overtaken the BNP's membership. Come January 2010, we would be level-pegging with UKIP. The Pirate Party has the potential to do what 'fringe' parties supposedly cannot do: build a genuine mass membership."
The news comes as weekend reports said individuals that take part in illegal downloading could have their internet access restricted and be fined as much as £50,000.
The reports said the harsher government plans to curb downloading was due to business secretary Peter Mandelson taking a firm stance on the issue after being pressured by entertainment bodies.
The June Digital Britain report was the latest government reaction to illegal downloading. It outlined plans to reduce illegal downloads by 80 per cent over the next two years by giving new powers to Ofcom.
Ofcom will work with internet service providers (ISPs) to target individuals sharing files with peers, and send them written warnings. If a warning does not work, the identity of the downloader will be given to the copyright holder who will then be able to take legal action.
However, it turns out the latest reports on supposed fines are false and the government's action on illegal downloading remains unchanged. At the moment the Digital Britain report is under consultation.
"The reports are rubbish," said a spokeswoman at the Department for Business. "The fine they mention relates to a different issue - the legislation proposed to tackle intellectual property crime."
An example of intellectual property crime the government wants to curb is cyber criminals stealing online bank details.
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