The term “outsider artist” is out of fashion these days, replaced by the more strictly factual “self-taught artist.” But in some cases the older phrase still seems more fitting, such as when describing someone who not only worked outside the established art world but also lived outside of mainstream society. Henry Darger, whose thousands of drawings and watercolors were discovered by his landlord only at his death in 1973, was that kind of outsider. So was Martín Ramírez.

A Mexican immigrant who spent the last 30 years of his life in California mental hospitals, Ramírez, who died in 1963, is considered by some critics to be one of the greatest artists of the 20th century. He never, however, profited from his success — nor, until recently, did any members of his family.

Last year, when a trove of 144 previously unknown drawings came to light, the artist’s heirs, who include a daughter in Mexico and 17 grandchildren, formed an estate and got legal representation. As a result of negotiations between the estate and the family in possession of the drawings — the descendants of a doctor who treated Ramírez at one of the mental hospitals — the estate now retains an interest in the works, which are being sold through the Ricco/Maresca Gallery, for prices that range from $50,000 to $350,000. Neither Frank Maresca, who is one of the owners of the gallery, nor a laywer for the estate, Eric Lieberman, would say what percentage of the proceeds the estate will get.

But even while exhibitions of these newly discovered works open on Thursday at Ricco/Maresca, and next week at the American Folk Art Museum, the legal status of another set of 17 drawings remains in doubt, as does the future of 10 Ramírez works in the collection of the Solomon R. Guggenheim Museum.

At issue is whether Ramírez, who was diagnosed as schizophrenic, was legally competent to give away his drawings, and whether doctors who treated him were permitted to accept them.

Ramírez was born in Jalisco, Mexico, in 1895, and immigrated to California in 1925. He worked on railroads and in mines and sent money home to his wife and four children. In 1931, he was arrested in Stockton, Calif., perhaps for vagrancy; a court eventually issued a judgment of insanity and placed him in the Stockton State Mental Hospital. In 1949, he was moved to the DeWitt State Hospital in Auburn, Calif.

During the years of his incarceration, Ramírez made crayon drawings on sheets of newsprint, grocery bags, or the long rolls of paper that were used to cover medical examination tables. He drew endless roadways, railroad tracks, and cityscapes, often populating them with horsemen who may represent the Mexican federal soldiers who brought destruction to the countryside in Ramírez’s youth.

During the 1950s and ’60s, at least two doctors at DeWitt — Tarmo Pasto and, later, Max Dunievitz — collected Ramírez’s drawings. It was Dunievitz’s daughter-in-law, Peggy Dunievitz, who contacted the Folk Art Museum last year about the 144 drawings she had inherited, which had sat in a box in her garage for almost 20 years.

Pasto, a professor of psychology and art who was a clinician on staff at DeWitt for a period in the early 1950s, eventually acquired about 300 of Ramírez’s drawings. He sold most of them, after the artist’s death, to the art dealer Phyllis Kind and the collector Jim Nutt. In 1955, he sent 10 drawings to the Guggenheim, but received no response. The museum unearthed them in the mid-1990s and formally acquisitioned them in 1997.

Pasto also sent 17 drawings to a graduate student in psychology, Maureen Hammond, who was writing her thesis on art therapy. Last year, after the Folk Art Museum put on a major exhibition of Ramírez’s work, Ms. Hammond, who is now 69, contacted Sotheby’s about selling the drawings at auction. She signed a contract with the auction house and sent the drawings to New York. In the meantime, however, Sotheby’s contacted Ramírez’s heirs, who claimed that they were the rightful owners of the artwork.

On August 8, Ms. Hammond filed suit against the heirs in California State Supreme Court, charging interference with contract and seeking a declaratory judgment regarding her title to the works. On August 11, the estate filed suit against Ms. Hammond in U.S. District Court in the Southern District of New York, demanding that the drawings be returned to it. Sotheby’s has said that it will hold the drawings until the dispute is resolved.

Mr. Lieberman and Ms. Hammond’s lawyer, Rick Richmond, each said in interviews that the parties were close to a settlement, but that a confidentiality agreement prohibited them from saying more. Mr. Lieberman also said that the estate is looking into its possible rights to other Ramírez works, including those at the Guggenheim.

“We of course are very aware of the works at the Guggenheim, and the estate may have some rights with respect to them,” Mr. Lieberman said. A spokeswoman for the Guggenheim declined to comment.

Of the 144 works in which interest is shared between the Dunievitz family and the estate, three have been donated to the Folk Art Museum, and almost 40 others have already been sold to collectors and institutions, Mr. Maresca said.

During Ramírez’s lifetime, his work was exhibited several times. In 1954, Mr. Lieberman said, his drawings were included in a show at the de Young Museum in San Francisco on the so-called “art of the insane.” Because he was a mental patient, Ramírez was not credited by name, but the San Francisco Chronicle mentioned in its review that the most striking artist in the show was “an aged Mexican with an innate gift for form, color, and pictorial organization.”

Mr. Maresca credited Phyllis Kind and Jim Nutt with doing “a terrific job,” in the 1970s and later, of promoting Ramírez and “placing the works in the right collections.”

Whether or not all the right people benefited, without such efforts “it’s a little like the proverbial tree falling in the forest,” Mr. Maresca said. “Someone creates an astounding body of work, and no one sees it, and it gets squirreled away somewhere with one person. The work is not less [remarkable] because of that,” he added. “It’s just that nobody knows it.”