At the heart of the complex affair are payments that Tapie, a larger-than-life figure in French business and politics, received in 2008 from the government over a dispute concerning the sale of sports company Adidas, once owned by Tapie.
Back in 2008, the French government approved a payout to Tapie in a rare out-of-court settlement which cost the taxpayer roughly 400 million euros (£353.52 million).
Orange's Richard was chief of staff to then finance minister Christine Lagarde at the time the award was granted. Lagarde is now head of the International Monetary Fund.
The trial concerns six people in all, said the source, who is an official in the judiciary who declined to be identified by name, which is standard practice in France on confirmation of judicial matters.
The source said Tapie and Richard faced charges of embezzlement and misuse of public funds.
Tapie's defence lawyer Herve Temime told Reuters: "I've been eager to fight this one out ... now all the cards will be on the table and we will be able to establish the truth. Not only was there no fraud but we will also see who was robbed and who did the robbing."
Richard also denied the charges, a spokesman said.
The case dates back to when Tapie sued the state for compensation after selling his stake in Adidas to then state-owned Credit Lyonnais in 1993.
He accused the bank of defrauding him after it resold its stake for a much higher price. With the case stuck in the courts, the two sides agreed to a private settlement and a 403 million euro payout to Tapie. Lagarde approved the settlement.
Tapie, now seriously ill, has fought one court battle after another but has already been ordered to pay back everything he was awarded.
Those rulings had prompted Tapie, the flamboyant owner of a Parisian mansion and a large yacht, to say recently that he was "utterly ruined".
IMF chief Lagarde escaped punishment in the same affair and kept her job, despite being convicted of negligence regarding the payout.
(Reporting Sophie Louet; Writing by Brian Love; Editing by Luke Baker and Robin Pomeroy)
By Sophie Louet