The suspects earlier contested the asset seizure, but the January 19 Riga District Court ruling is understood to be final.
In 2014 the Criminal investigators with the state Customs Service seized about 100 tonnes of illegal petrol from the the Trest chain of fueling stations.
Investigators say that about €2m in various currencies were also seized in the case, with the police saying that in a single instance they seized more than €800,000 at the residence of an involved person.
The fuel should have been exported, but was allegedly diverted through various Trest retail fueling stations, as reported by LTV's De Facto.
It came from Russia or Belarus and was meant to be shipped further. However, it wound up in the gas tanks of Riga drivers through a convoluted scheme.