Employees at insurer PZU received shares in the company in 1999 with the restriction that they could not be sold for two years. No doubt needing the cash, some employees sold their stock unofficially and a thriving trade built up. It has now come to light that fraudsters also profited from this to put forged certificates on the market. It is believed that around 20,000 forged certificates are now in circulation. Prosecutors and the stock exchange commission KPWiG are looking into the matter.