A French court ruled Tuesday that Irish budget airline Ryanair must pay 8.1 million euros ($10.3 million) in damages along with 200,000 euros in fines for breaching French labour law.
An appeals court found the company guilty of paying workers under Irish contracts to save money on payroll and other taxes.
In October 2013, Ryanair was ordered to pay nearly nine million euros in damages and interest.
The airline was charged with avoiding paying payroll and other taxes, as well as preventing workplace councils from functioning and hampering employees' access to unions.
Ryanair appealed the ruling in June 2014.
Social charges in France are at around 40-45 percent, compared to 10.75 percent in Ireland.
The airline will have to pay damages to trade unions, France's social security system and pilots among others.
The case is focused on a facility in Marignane, near Marseille in the south of France.
The company based four planes and 127 employees at the site without applying French labour law or filling out tax declarations in the country.
Ryanair argued that it did not have a permanent base in the area and that it was entitled to keep its workforce on Irish contracts, but prosecutors said its claim was not credible because the workers were living locally, and the airline had offices there.