PB Technologies, which has stores across New Zealand, used Trade Me data to spam customers.

It has agreed to stop engaging in the practice, after cutting a deal with the Department of Internal Affairs, which says the IT and consumer technology chain breached the Unsolicited Electronic Messages Act.

PB Tech has signed an enforceable undertaking with the DIA after it was found to have collected Trade Me customer details during trades and then sent them unsolicited messages.

"The undertaking outlines PB Tech's agreement to no longer send commercial electronic marketing messages to customers without their consent," the DIA's Toni Demetriou


"Future compliance was a key factor in the department's decision. The agreement allows us to work with PB Tech on their compliance obligations, but also take the matter to court if the agreed terms are breached."

Demetriou says cases like these set a good example for other businesses.

"We hope cases like these encourage other organisations to look at their electronic messaging practices and help educate the public on the rules around any messages they receive.

PB Tech general manager Darren Smith told the Herald the company had sent the emails for years and didn't know it was in the wrong.

"It wasn't intentional, we didn't quite understand the rules," Smith said.

It came to light when members of the public complained to the DIA, he said.

He understood that about five people complained.

There have been relatively few official sanctions for New Zealanders or their businesses sending spam.

In 2015, an Australian businessman was fined $95,000 in Auckland for sending almost a million spam emails to New Zealanders after buying addresses from a data company.

Wayne Mansfield of Perth had more than 80,000 email addresses in his database to which he sent unsolicited messages about his business seminars over two months.

In 2009, A Kiwi "mastermind" behind an international spam network was ordered to pay US$15.15 million ($21.33m) by a US federal judge.

Lance Atkinson, originally from Christchurch, was identified by anti-spam organisation Spamhaus as the ringleader of the world's largest spam gang, marketing male enhancement pills, prescription drugs and weight-loss pills, the US Federal Trade Commission (FTC) said at the time.