Lincolnshire Trading Standards are warning people to be vigilant after a spate of fake products being sold in the workplace.
The sector has sent out 100 letters and posters to local businesses to make them aware that staff may be using using the workplace to sell the goods.
Most complaints Trading Standards have received are relating to CDs and DVDs, but products like clothing, handbags and cigarettes are also being sold.
Divisional Manager Nick Dawes said: “Our work in car boot sales and markets has resulted in thousands of pounds worth of counterfeit goods being seized with several prosecutions and more pending.
“Some of the illegal traders at these markets have totally stopped, however many seem to have moved their sales base.
“There’s no particular type of business involved, complaints have been received from businesses ranging from small transport companies to very large food factories.
“Far from being a victimless crime it is local jobs in the manufacturing, distribution and retail sectors that suffer.
“Sellers of counterfeits can face a heavy fine, imprisonment and a criminal record. Those caught selling fake goods at their place of work also risk losing their jobs.”