David Berger, who called himself a "people's lawyer," was best known as one of the pioneers of class-action lawsuits. After leaving the Philadelphia City Solicitor's Office for private practice, he recovered billions of dollars from the government, big oil companies, and Wall Street bankers for legions of small clients.

Mr. Berger, 94, who of died of pneumonia Thursday in Palm Beach, Fla., won major cases in the Three Mile Island nuclear power accident, the Exxon Valdez oil spill, and the Drexel Burnham Lambert junk-bond scandal. His firm won a $2 billion settlement from the government on behalf of the bankrupt Penn Central railroad and thousands of shareholders.

"He was a bright, bright lawyer," said Richard A. Sprague, the prominent Philadelphia criminal attorney who practiced with Mr. Berger in the 1970s. "The world didn't realize the potential of class-action litigation until Dave Berger came along."

But Mr. Berger was more than an innovator of complex litigation that allowed lawyers to collect many small clients together to fight some of the world's most powerful defendants.

As city solicitor under Mayor Richardson Dilworth in the late 1950s, Mr. Berger was instrumental in establishing major public institutions, including SEPTA and the Philadelphia Industrial Development Corp.

A former chancellor of the Philadelphia Bar Association, Mr. Berger was active in Democratic party politics - he lost the 1969 race for district attorney against Arlen Specter.

"He was a giant in his field," said Gov. Rendell, who remembered speaking with Mr. Berger by telephone three months ago. He asked about the Philadelphia mayor's race, the governor said.

"He had a deep and abiding passion about making Philadelphia better," Rendell said.

The son of immigrant Jewish peddlers from Austria, Mr. Berger was born in Archbald, a small town near Scranton. He graduated in 1936 from the University of Pennsylvania Law School, first in his class, Order of the Coif, and as a member of the law review.

His legal work made him rich.

While continuing to make courtroom appearances into his 80s, he commuted between Philadelphia and his mansion in Palm Beach, and was active in the social circuit. Prince Philip and Prince Edward served as groomsmen at his 1997 wedding to his second wife, the socialite Barbara Wainscott, in New Zealand.

"He was very creative, very energetic," said his law partner, Laddie Montague, with whom he formed the 30-partner boutique law firm Berger & Montague in 1970. "He loved the law, he loved tennis, he loved life. He was a doer and a creator, just look at his record."

In a 1985 interview, then-Temple University president Peter Liacouras said Mr. Berger "is one of the premier antitrust lawyers in a city that is renowned for exceptional antitrust lawyers. He is resourceful and effective."

Mr. Berger arrived in Philadelphia in 1929, a few months before the stock market crash drove the family store into financial ruin. Mr. Berger's son Daniel, a partner at the Philadelphia law firm, said his father earned his way through Penn with a job at the Jewish Student Center that paid him a dollar a day, plus an apple.

"He was strong-willed," the son said. "He never gave up and he never gave in, even if he lost a case. He never surrendered. He had tremendous psychological strength."

After graduation, Mr. Berger served as a special assistant to the law school dean and kept a lifelong connection to the university. He was a member of the Board of Overseers of the Law School and an associate trustee of the university.

He worked as a law clerk for the Pennsylvania Supreme Court and later for the U.S. Court of Appeals for the Third Circuit before joining the Navy during World War II. He served on aircraft carriers in the South Pacific.

He is a survivor of the sinking of the Hornet in 1942, and later was chosen by Adm. William F. Halsey to serve on his personal staff when the admiral became commander of the South Pacific. Mr. Berger was ultimately promoted to commander, and was awarded a Silver Star.

In New Guinea during the war, he met Marine Capt. Richardson Dilworth of Philadelphia and they struck up a friendship.

"They promised that if they survived the war, they would go back and reform Philadelphia's government," said Daniel Berger.

Dilworth appointed Mr. Berger city solicitor in 1956. During his term, President John F. Kennedy appointed him to a committee to develop high-speed rail lines in the Northeast Corridor, an idea that later became Amtrak.

Mr. Berger returned to private law practice in 1963.

Soon he and Harold Kohn, another renowned Philadelphia trial lawyer, began developing class-action suits under federal antitrust laws. The laws allowed attorneys to sue on behalf of many clients. The only requirement was that a judge had to certify that the clients all had similar claims - that they were members of the same class. The suits became instrumental in spurring changes in many areas, including consumer products, environmental practices, and medical practices.

One of his first suits, said Montague, was on behalf of municipal governments against suppliers of rock salt, alleging price-fixing.

Mr. Berger was recognized repeatedly for professional achievements, and served on numerous legal committees and philanthropies.

He served on the U.S. Supreme Court committee to draft the Federal Rules of Evidence. He was a fellow in American College of Trial Lawyers, the International Society of Barristers and the International Academy of Trial Lawyers. He was a life member of the Judicial Conference of the Third Circuit, and the American Law Institute. And he was an appointee of former President Bill Clinton to the U.S. Holocaust Commission.

Mr. Berger, who was diagnosed with stomach cancer in 2000 and successfully fought the disease, retired in 2004, when he began to suffer early stages of Alzheimer's disease.

In addition to his son Daniel, Mr. Berger is survived by another son, Jonathan; two grandchildren, and two younger brothers. He is also survived by two former wives: his first wife, Harriet; and his second wife, Barbara, whom he divorced in 2004.

A private funeral will be held Tuesday in Scranton.

Contact staff writer Andrew Maykuth at 215-854-2947 or amaykuth@phillynews.com.