Casino succession is in question at Macau gambling empire of ailing Stanley Ho

No single person holds greater sway over the Macau casino industry than Mr. Ho. While his four-decade monopoly on gambling in Macau ended in 2002 when foreign competitors were allowed in, his casinos hold the largest market share in the former Portuguese colony, with about a quarter of the city's gambling revenue. His views are closely watched by analysts, competitors and regulators.

"Politically and socially, Stanley Ho's absence comes at a very difficult time, both for his own companies as well as for the whole Macau gambling industry, since he has long been the most influential figure in the business," says Carlos Lobo, a gaming analyst and former legal adviser to the Macau Gaming Commission.

His condition was unclear Thursday, and Mr. Ho's office didn't reply to calls and emails. Several Hong Kong news outlets said Mr. Ho had undergone brain surgery to remove a blood clot. Janet Wong, a spokeswoman for Mr. Ho's office, on Tuesday confirmed that he had undergone surgery, without elaborating.

The openly polygamous Mr. Ho has 17 children, which include two children - Pansy, 45, and Lawrence, 32 - who have each teamed up with foreign partners to open casinos in Macau. At the end of July, casinos affiliated with the Ho family controlled about 53 % of gambling revenue in Macau, which totaled about us$ 14 billion last year, making it the world's largest casino market.