Two people who received "third strikes" for pirating music over the internet under the controversial "Skynet" copyright law have been let off the hook.

About 2000 infringement notice have been issued to internet users for piracy since the law, designed to combat illegal file sharing, took effect in September, telecommunications firms said. All were in response to requests from the Recording Industry Association of New Zealand (Rianz), which represents major record labels.

TelstraClear and Vodafone said in April that they had each issued third and final "enforcement notices" to customers, which meant Rianz could have brought either person before the Copyright Tribunal, where the maximum possible fine is $15,000.

However, the opportunity for Rianz to take action had now lapsed, a source confirmed.

TelstraClear issued the third-strike notice to its customer on April 12 and Vodafone's third strike was reported a week later.

Under the terms of the Copyright Act, Rianz had only 35 days after those dates – no later than last Thursday – to take either case to the tribunal.

A Justice Ministry spokesman said the Copyright Tribunal had not received any applications for enforcement action.

According to the act, the expiry date means all infringement notices issued to both customers are annulled and they will be back on a clean slate of "zero strikes".

Vodafone spokeswoman Michelle Baguley said last month that its customer was talking directly with Rianz after contacting Rianz through his or her own volition.

TelstraClear would have been obliged to forward details of its customer to the Copyright Tribunal only if Rianz had decided to take a case.