A.N. Pritzker, 90, a billionaire philanthropist and the founder of one of the nation's foremost business empires including the worldwide Hyatt hotel group, died Feb. 8 at a hospital in Chicago of a cerebral vascular occlusion.

Mr. Pritzker scorned traditional and time-tested ways of doing business, and often boasted of how he made billions by ignoring the advice of lawyers and experts.

As more and more companies turned to public sales of stock to build revenue, Mr. Pritzker took the opposite tack, believing it was more important at times to have room to negotiate.

"We don't believe in public business," he said. "Any public corporation that seeks vast expansion has a conflict with shareholders . . . . We take a book loss on a building or a hotel, but how do you keep the shareholders fully informed of what you're doing? You can kill a deal revealing information."

Forbes magazine recently put the Pritzker family's worth at $1.5 billion, and one recent count of its holdings, most of them under the umbrella of the family owned Marmon Group, numbered 266 companies and subsidiaries.

The best-known of the group are the 140 Hyatt hotels, Braniff Airlines and McCall's magazine; but the Pritzkers also own casinos, a law firm, cable TV systems and companies that make everything from railway box cars to aluminum forging for missiles.

Even after relinquishing control over most of the enterprise five years ago to sons Jay, 62, and Robert, 58, Mr. Pritzker continued to keep tabs on the family's progress from behind a paper-cluttered desk on the 30th floor of a Chicago bank building. A third son, Donald, died of a heart attack in 1972 at the age of 39.

Mr. Pritzker handled many of the family's philanthropic activities from his office, dispensing millions of dollars a year to various charities and causes.

Those gifts ranged from a $12 million check he gave to the University of Chicago for its Pritzker School of Medicine to the annual Pritzker Architecture Prize, which provides architects a gift of $100,000 for creative endeavors in architecture.

Abram Nicholas Pritzker was born Jan. 6, 1896 in Chicago.

A 1920 graduate of Harvard Law School, Mr. Pritzker and his younger brother, Jack, left their father's law firm in 1936 to try their hand in the commercial world.

He purchased the Hyatt Regency Hotel in Atlanta, coming into the deal after the original developers' financing had been canceled.

He ended up with "a world-beater in that hotel," he said. "The people who sold it lost a profit of at least, six, seven, eight million dollars because every hotel we have we owe to that one."

Mr. Pritzker had been working on an autobiography and said in a recent interview: "A lot of people say I brag a lot, but what the hell, I got a lot to brag about."

In addition to his sons, Pritzker is survived by his second wife, Lorraine.