John Gilligan and his family have lost their Supreme Court appeal aimed at preventing the sale of their properties by the Criminal Assets Bureau.
The properties in question include the Jessbrook equestrian centre and a number of houses which the CAB says are the proceeds of crime.
John Gilligan had asked the Supreme Court to rule that proceeds of crime findings by the High Court in 1996 and 1997 were not final orders.
His family had argued they were entitled to a fresh hearing of the High Court proceedings which declared their properties to be the proceeds of crime.
The decision means the CAB can now apply to the High Court under the proceeds of crime act to dispose of the properties which also includes houses in Lucan and Blanchardstown.