ACMA levied the fine after an investigation revealed that Tiger had not removed customers from its email marketing list despite unsubscribe requests.

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The Spam Act requires that commercial marketing emails must contain a functional unsubscribe facility. The fine is a wake-up call for business to test their email unsubscribe function regularly, said ACMA deputy chairperson Richard Bean.

In the 2011-12 financial year, ACMA reported a sixfold increase in spam reports to the organisation, and issued 4200 informal warnings, seven formal warnings and three court-enforceable undertakings related to spamming by Australian organisations.

Australia is responsible of 0.26 per cent of spam worldwide, according to security vendor Sophos.