“Showing young artists isn’t a way to make a lot of money but I do it because I love art and it’s fun to help young artists,” the dealer Jack Tilton said in an interview last year with the Art Dealers Association of America (ADAA). Throughout his career, which spanned more than 40 years, Tilton was relentless in shining a spotlight on both emerging artists and work that he believed had been wrongly overlooked. In an era that has come to be defined by ever-expanding mega galleries, he was a maverick. Tilton passed away this past weekend, ARTnews has learned.

Despite helping to launch the careers of numerous mainstays of today’s contemporary art scene, he operated on a relatively modest, personal scale, promoting his latest enthusiasms out of an Upper East Side townhouse over the past decade. His death, which has been confirmed with people who were close to him, marks the end of a uniquely original career. The details of his passing were not immediately available, but he had had Parkinson’s Disease since at least 2010.

Tilton cut his teeth from 1976 to 1982 at the storied Betty Parsons Gallery, which showed Abstract Expressionist giants as well as an eclectic group of other artists, from Forrest Bess to Richard Tuttle. “She felt art should be democratic,” Tilton told the New York Times in 1992, describing an ethos to which he also adhered. “The gallery was not just about stardom and making money. She wanted to show what she wanted to show.”

In 1983, Tilton opened his own gallery in Parsons’s old space, on West 57th Street in Manhattan, and in the 1990s he relocated to Greene Street in SoHo. In those early years he gave shows to pivotal figures like Marlene Dumas, Nicole Eisenman, Francis Alÿs, and Wangechi Mutu. In 1999 he opened a Los Angeles gallery with Bennett and Julie Roberts called Roberts & Tilton, which is located in Culver City. The next year he formed a partnership with Anna Kustera. In 2005, he moved his gallery to a tranquil townhouse on the Upper East Side. He also ran a residency for artists in Tong Zhoa, China, called China Project.

Tilton Gallery, which he ran with his wife, Connie Rogers Tilton, currently has on its roster a multi-generational band of artists, both emerging and established, from Brenna Youngblood, Egan Frantz, and Yashua Klos to John Outterbridge, David Lynch (the director, who also paints), and Ed Clark, the veteran African-American artist whose 2014 show at the gallery was organized by David Hammons, another artist whose work Tilton supported.

Asked in that ADAA interview last year about what made him decide to represent an artist, Tilton said, in his characteristically low-key way, “There’s no magical answer to that question but we try to show people who create meaning, or do something, for our time—who are of the moment.”

Sarah Douglas contributed reporting.