Online tradesman marketplace Service Seeking Pty Ltd has been hit with a fine for spamming people via SMS without consent.

The AU$50,400 infringement notice is for sending unsolicited text messages, for failing to clearly identify who authorised them to do so, and for not including an unsubscribe statement.

The fine follows an investigation by the Australian Communications and Media Authority (ACMA) into consumer complaints about Service Seeking's marketing practices.

"Businesses that use SMS marketing must make sure the recipient has given permission to be contacted. In this case, the business sent commercial messages to phone numbers obtained from an online directory without the consent of the accountholder," ACMA chair Nerida O'Loughlin said in a statement.

The ACMA has been targeting consent-based marketing. The penalties for breaching Australia's spam rules can be serious for businesses; if found breaking the rules, the ACMA can seek a civil penalty and/or injunction from the Federal Court; give an infringement notice; accept a court enforceable undertaking; or issue a formal warning.

The Australian Taxation Office (ATO) is looking to do a mass mail-out of its own, turning to the market for a third-party email provider to send over 5 million emails out to Australians.

"The primary use of this service will be for the [ATO's] business teams to send digital newsletters, ad hoc urgent alerts, and targeted information emails to separate, targeted user bases, often at the same time," the Approach to Market (ATM) documentation explains.

"The [ATO] expects to send more than 5 million emails per year through the service, reaching approximately 250,000 unique email addresses (in total across all subscriber groups). Each subscriber group will contain up to 45,000 addresses but could contain up to 100,000 addresses.

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