Thousands of people who have illegally downloaded movies or television shows from the Internet are nervously waiting to see if they have been targeted in a crackdown on online piracy.

The move comes after the Federal Court ruled internet service providers should hand over to a US film studio the names and addresses of 4,726 customers who allegedly shared pirated copies of the Oscar winning film Dallas Buyers Club. Ironically, it's a film about blackmarket deals.

The decision means the Hollywood company now has the authority to pursue thousands of Australian Internet account holders for damages over the breaches of copyright.

Anneka Frayne, solicitor at Stacks Law Firm, says the decision is likely to make hairs stand on end of anyone who has illegally downloaded a film, TV show or songs.

"The decision has put everyone on notice that there are real consequences to piracy and breaching copyright," she said. "People need to know that taking copyrighted material from the Internet such as a movie without paying for it can be theft."

Ms Frayne pointed out that movies and TV shows like Game of Thrones cost a lot of money to make. Fans who steal the product without paying for it are taking money from the actors, set workers and everyone involved in making the film.

"Imagine you have written a book or recorded your own song. If people just take it without paying for it they are taking away your livelihood. It is a criminal offence just like stealing."

She urged anyone who receives a letter from representatives of the Dallas Buyers Club studio or other copyright holders to seek their own legal advice. Owners of copyright can sue for damages over copyright infringement.

There are moves afoot to strengthen anti-piracy laws even further to include criminal penalties for some forms of copyright infringement. Already there are potential five year jail terms for "commercial scale" copyright infringement under the 2004 Australia-US Free Trade Agreement. Some experts say the wording on the law is such that it might even apply to individuals who are just sharing films online.

Anti-piracy groups are proposing a new 'three strikes' policy under which account holders who break the law three times in a 12 month period would be referred to copyright holders who could take legal action.

"People should always be mindful of where you download your films, music or other things that might be someone else's intellectual property," Ms Frayne said.

"Always use legitimate downloading forums such as iTunes, otherwise may be at risk of being sued. This is becoming a serious legal issue."