The consumer watchdog says publicly listed price comparison website iSelect misled and deceived customers for two years by recommending energy retailers that paid it higher commissions.
The Australian Consumer Competition Commission alleged on Friday that since at least November 2016, iSelect had claimed consumers using its website would benefit from iSelect comparing all plans available from its partner retailers in a specific location.
The ACCC said during this period, iSelect also claimed that it would recommend the most competitive plan to consumers.
"But we claim they were actually favouring some partner retailers over others, such as those on its 'Preferred Partner Program' who were allowed to have more plans available on the iSelect website that excluded and targeted certain consumers," ACCC chair Rod Sims said.
"These preferred retailers paid iSelect higher commissions."
In a statement tot the ASX, iSelect said it took its obligations under Australian Consumer Law very seriously and had processes in place to ensure compliance.
"iSelect has worked cooperatively with ACCC throughout its investigation," the company said.
"As the matter is now before the Federal Court, the company is unable to make any further comment".
The ACCC said it is seeking pecuniary penalties, injunctions, declarations, correctives and costs.
It said more than nine million Australians visited the iSelect website in FY2017 with six million recommendations to consumers over all categories.