A French court will rule today on whether Ryanair should face tens of millions of euros in fines over charges of breaking labour law.
The low-cost carrier faces several charges including registering French workers as Irish employees and preventing access to trade unions.
The case centres around a facility operated by the company near Marseille.
Prosecutors are urging the court to confiscate four Boeing 737s based at the site.
If the court agrees, Ryanair would have to pay the equivalent value of the four planes, which cost €50m each.
The airline says it expects a "negative ruling" and is already planning an appeal.