A court ruled on Tuesday that eight workers involved in the “bossnapping” were to be sent to jail for nine months each.
Two of the workers were also convicted of assault, but were not given any additional prison time.
The hostage situation played out in northern France's Amiens over 30 hours in January, 2014, during a period of strife when 1,173 workers were facing the axe.
Employees at the plant forcibly took production manager Michel Dheilly and Human Resources director Bernard Glesser hostage, with union representatives promising to keep the two men captive until better terms were offered for the workers.
Workers wedged a tractor tyre up against the meeting room door to prevent the hostages from getting away.
The severity of the sentences angered unions.
“We think the decision is very unjust and we are going to appeal,” said one of those sentenced, Hassan Boukri.
Another worker, Reynald Jurek, said the verdict was “purely political”.
For their part the CGT union said the verdict was “unncceptable” and claimed the government was trying to “intimidate workers who were fighting for their rights and their jobs”.
Socialist MP Yann Galut took to Twitter to share his astonishment at the rare move to jail workers for an act that was part of a labour dispute
“I want the same severity against rogue bosses,” he wrote.
The trouble at Goodyear, which had rumbled on for six bitter years became a sort of poster child for poor labour-management relations and the difficulties of investing in France.
After a failed takeover bid from Titan International's chief executive Maurice Taylor, he publicly ridiculed French laws and trade unions and suggested French workers were lazy.
On the day the Goodyear execs were released a shocked Taylor said: “called the act a “crime” and said it would be considered a “kidnapping” in the United States.
“These people should be arrested and prosecuted,” he said about the workers. “It’s a very serious crime, you could get life in prison. But in France, your government does nothing, it seems crazy.”.
While holding bosses prisoner is not a new phenomenon in France – the move became rampant in 2009 during the height of the economic crisis – it is somewhat rare for unions to be taken to task for such militant action.
It is rare in France for workers to be sentenced to prison for such acts even though they are punishable by up to 30 years in prison.
“Bossnappers” risk fines of 75,000 and five years in jail, unless the captivity lasts from than a week and includes violence, at which point the sentence can theoretically reach 30 years.
When postmen “bossnapped” managers from La Poste in 2010, judges were lenient on the aggressors citing “desperate situation”.
Opinion: Why the French are entirely right to go on strike all the time. Photo: Boris Horvat/AFP