Kogan has been found to have misled consumers during its 2018 tax time sales promotion, the Federal Court has found.
The business was found to have breached consumer law by making false and misleading representations about the sale and savings.
Between 27 to 30 June 2018, Kogan advertised that consumers could use the code 'taxtime' to save 10 per cent on their purchases.
The eTailer advertised this sale on its website, in emails sent to more than 10 million consumers and in text messages sent to 930,000 consumers.
However, the Court found that Kogan had increased the prices of more than 600 products immediately before the promotion - in many cases, increasing the price by at least 10 per cent.
Towards the end of the sale, Kogan sent emails to consumers encouraging them to make a purchase during the sale and included statements like, "48 hours left!" and "Ends midnight tonight!"
Kogan had also reduced the prices of these products shortly after the promotion ended, many back to their pre-promotion prices.
ACCC chair Rod Sims said that all businesses must ensure that sales offer consumers genuine savings.
"We brought this case because we were concerned that the advertised price reductions were not genuine savings.
"Many consumers who took up the offer on one or more of the 600 or so products in many cases actually paid the same as, or more than, what they would have paid immediately before and after the promotion.
"All businesses must ensure that their advertisements do not mislead consumers about the nature of a promotion, and that any promised savings are genuine," he said.
This is not the first time Kogan has been found to have raised the prices of products prior to a sale, paying $32,400 in penalties in 2016 for a Father's Day 2015 promotion on it's eBay store which offered consumers a 20% discount.
In that case, Kogan was found to have raised the prices on three computer monitors before or at the start of the promotion.
While consumers did recieve a 20% discount, the price they paid was only 9% off the previously advertised prices.
Similarly, once the sale ended, the prices returned to the lower rates they were at prior to the promotion.
In a statement, Kogan said that the 2018 tax time promotion was not intended to mislead any customers.
"The profit derived by the Company from the promotion was immaterial and the ruling will not have any adverse impact on the Company's promotional activities, as the Company updated its promotional activities in 2018.
"The promotion was not intended to mislead any shoppers, and was implemented in order to allow customers access to lower prices than the prices that applied without the coupon or promotion.
"At all times, the Company has been focussed on making the most in-demand products and services more affordable and accessible for all Australians," Kogan said.
A hearing on relief, including penalties, will be held at a later date.
The ACCC is seeking declarations, injunctions, pecuniary penalties, corrective notices and costs.
Kogan is currently reviewing the ruling of the Federal Court and may provide a further update once its review is complete.