Services will be private for Frederick W. Anton III, 83, the leader of the Pennsylvania Manufacturers' Association, who was found dead in the Delaware River on Thursday.

"There will be a future announcement about how to remember my dad," said daughter Sarah D. Anton.

A well-known fixture in Pennsylvania politics and Philadelphia city life, Mr. Anton had been reported missing Wednesday from his North Christopher Columbus Boulevard condo.

Although generally a cheerful person, he had been depressed for a month after becoming ill, his family said. A city health department spokesman said Monday that the cause of death is pending while further tests are done.

David N. Taylor, association president, said the statewide trade group and pro-business lobby had received many condolences from those who knew and had worked with Mr. Anton.

"No matter who you were, they're telling me — a junior aide or campaign worker — he always treated you with kindness and respect, like you were a real person," Taylor said. "Even if you disagreed with him, he treated you with respect."

Elected officials such as former Gov. Tom Ridge and Sen. Pat Toomey (R., Pa.) also reacted to Mr. Anton's death.

"Michele and I were deeply saddened to learn of the passing of our friend and Pennsylvania political icon, Fred Anton," Ridge said.

"Fred played a critical role in helping us to advance our pro-business agenda during my years in Harrisburg. He was always thoughtful and could be counted on to find creative solutions to challenging problems."

"I was shocked and deeply saddened to hear about the passing of Fred Anton," said Toomey. "Fred was an icon in Pennsylvania's conservative movement and served as a mentor to many, including myself."

Born in Philadelphia, Mr. Anton was a resident of the area all his life. He graduated from Haverford High School, Villanova University, and the Villanova School of Law, and was a Marine Corps veteran.

Mr. Anton joined the manufacturers' group in 1962 as an attorney with its insurance provider handling workers' compensation matters. He became leader of the insurance provider in 1972, and of the association as a whole in 1975.

In a signature gesture dating back to 1981, he hosted a bipartisan luncheon at the Metropolitan Club in New York City on the Saturday of the Pennsylvania Society's annual dinner.

Leading political figures from both parties attended each year, and that tradition is expected to continue.

"Hopefully, they will make this a memorial to Fred showcasing what he did," said his friend Sam Katz, a Philadelphia filmmaker and former mayoral candidate.

In a 2012 profile, the Pittsburgh Post-Gazette pointed out that although Mr. Anton wielded political clout because of the leading companies and thousands of workers he spoke for, he was largely unknown to the public.

"He generally works behind the scenes, on the phone or in personal meetings with legislators rather than calling news conferences, so that few outside corporate circles and Republican political ranks have heard of him," the paper wrote.

Katz, who wanted Mr. Anton to run his primary mayoral campaign in 1990, said he camped out in Mr. Anton's office until he got his attention.

"He said he would chair the campaign only if the party picked me — and it endorsed Ron Castille — but I maintained my relationship with Fred for 27 years," Katz said.

There were two Mr. Antons, Katz said. One was "Harrisburg Fred," a conservative and political powerhouse "back in the day when Pennsylvania was a maker of everything."

"He was very effective at raising money. He loved being around power, and he enjoyed the give and take of the political process, and was very good at it."

The other was the more mellow "Philadelphia Fred," who supported Arlen Specter, even though the U.S. senator switched registration from Republican to Democrat in 2009 to run in the 2010 primary against Joe Sestak. Sestak defeated Specter, ending his career.

"Fred had sharp elbows and could be a handful in my mind, but he was a really terrific guy. He wasn't easy to know, but once you did, you would know him for life," Katz said.

Outside the political arena, Mr. Anton was an enthusiastic patron of the arts. He underwrote a residency for a playwright at the Arden Theater Company and was a supporter of the Free Library of Philadelphia.

"Whenever there was an author's night at the library, he would go to hear the author," Taylor said.

Mr. Anton also loved golf. He played at various courses, including the exclusive Pine Valley. He caddied at the U.S. Open when it was played at Merion in 1950.

"When one of the big national golf tournaments came through, he was there," Taylor said.

Mr. Anton was married to Elizabeth Daniels Anton. They divorced; she survives. Besides his daughter, he also is survived by a son, Frederick W. IV; his partner,  Emily Ryan; and a sister.

Memorial donations may be made to the Arden Theatre Company via, or the Free Library of Philadelphia via