Cannes Lions Festival Plays Host to a Messy Business Divorce

The picturesque beachfront of the French Riviera is an unlikely place for a bitter rivalry. And yet, as the elite of the media and entertainment industries flocked to Cannes this week for the world’s top ad festival, two heavyweights squared off.

On one end of the beach where ad deals are struck over glasses of rosé: Michael Kassan, 74, a ringmaster of the marketing industry. His MediaLink consulting firm helped transform the annual Cannes Lions International Festival of Creativity into a splashy exponent of the schmoozer-industrial complex.

On the other end: United Talent Agency, the Hollywood power broker that bought MediaLink in 2021. Last spring, UTA and Mr. Kassan parted ways, with the company filing a lawsuit accusing him of treating MediaLink’s bank account as his “personal slush fund,” wasting millions of dollars on lavish purchases. Mr. Kassan has called those purchases legitimate business expenses.

The case, whose expense details scandalized the media and ad industries, is in arbitration. But it has cast a shadow this week over the Croisette, the baking-hot thoroughfare where allies of both rivals discussed the messy business divorce in palatial hotels, ornate ballrooms and private shuttles to breathtaking hilltop villas.