The New South Wales Supreme Court has ruled the state's Health Care Complaints Commission should not have issued a public warning against a prominent anti-vaccination group.

The Australian Vaccination Network (AVN) took the court action after the commission (HCCC) after the warning against it was issued in July 2010.

The HCCC issued the warning after the network failed to comply with its recommendation to disclose on its website that the group's purpose was to provide anti-vaccination information.

The network argued the commission did not have the authority to issue such a warning.

This morning the Supreme Court has agreed the HCCC was not within its jurisdiction to do so.

In 2010 the commission said it had established the network's website contained incorrect and misleading information, and quoted selectively from research.