The Barclay brothers claim that they were defamed by an article published in The Times in November 2004. The article was headlined "Twins who swoop on owners in distress", and in later editions the last word was changed to difficulty.
Robert Thomson, the editor of The Times, and Dan Sabbagh, media editor, are in court in the French capital, where they deny the charges.
The Barclays are able to pursue their claim through the French legal system because The Times sells around 3,500 copies in France. The brothers, who have a house in Monte Carlo, bought the Telegraph Group in June 2004.
Compared with the UK, French libel awards are less punitive. The maximum fine that can result from a conviction is €12,000 (£8,200), and if the court orders a defendant to pay damages the sums are not as high as have been seen in the UK.
An important feature of the case is likely to be the interpretation of the French translation of the 300-word article, with The Times' legal team set to argue that the other side has exaggerated the wording in translation to imply that the Barclays pillage companies.
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