A woman sold counterfeit coloured contact lenses which posed a "public health concern", a jury has heard.
Investigators bought the Freshlook Colorblends from Alluring Lenses - run by Zahra Gillani over Facebook - in 2018, Newcastle Crown Court was told.
Analysis showed each of the three sets was fake. Ms Gillani, 31, denies three counts of selling and one count of possessing counterfeit goods.
The court heard she will argue she believed them to be genuine.
An investigator for TM Eye Ltd, a private firm that targets counterfeit trade, bought three colours of lenses - sterling grey, brilliant blue and gemstone green - in March and April 2018.
Each set cost £15 and they were found to be counterfeit versions of the Novartis AG lenses, the court heard.
On 3 July 2018, a stock check on her website revealed she was offering 496 lenses for sale worth £12,340.
Two days later, the investigators raided her home on Gowland Avenue in Newcastle where they seized a large quantity of lenses as well as Alluring Lenses labels and packaging.
A number of the lenses, which she had bought from China and South Korea, were tested and all were found to be counterfeit, prosecutor Julian Goode said.
"It's important because companies such as [Novartis AG] lose a significant amount of revenue when their items are not sold and counterfeit items are sold in their place," Mr Goode told the court.
"In this case, there is a public health concern as lenses that are counterfeit have not been subjected to the rigorous checks one would expect from genuine products produced by genuine companies."
He said "there is no dispute" the items were counterfeit, but Ms Gillani claimed she sold them believing them to be "genuine and legitimate".
The court heard she declined to comment when interviewed by TM Eye officers except to say: "I've always believed I was selling legitimate products."
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