The Gotham Book Mart & Gallery — the venerable Midtown bookshop with its recognizable metal sign “Wise Men Fish Here”— is facing choppy waters. A sign posted on the lower right side of its door at 16 E. 46th St. announces: “The landlord has legal possession of these premises pursuant to warrant of Civil Court. For information, contact landlord or agent immediately.” Other signs in the windows say, “Wise Men and Women Gone Fishin’ — Vacation Time — Be Back Soon — (knock for deliveries).”

Gotham is no ordinary bookstore. Many famous writers have walked its charming aisles packed with new and used books. On the store’s blue bookmarks is a quote from Dick Cavett: “Gotham Book Mart should be declared a national cultural treasure.” John Updike called it his favorite store in North America, and the Associated Press called it “an American monument” and “a sort of Carnegie Hall of modern literature.”

Asked what the legal notice meant, a New York-based lawyer specializing in real estate and commercial litigation, Mitchell Cantor, said it was an eviction notice from a marshal and “the tenant broke some condition of the lease or failed to pay rent or both.” On a New York Department of State Division of Corporations Web site, the landlord is listed as 16 East 46th Street Property LLC.

Two people in the antiquarian book world, who declined to be named, said the proprietor of Gotham Book Mart & Gallery, Andreas Brown, was “in negotiations.” Repeated calls to Mr. Brown were not returned.

“The bookshop is one of the great treasures of our city,” said the executive director of the Poetry Society of America and poetry editor at the New Yorker, Alice Quinn. Her book of new uncollected poems of Elizabeth Bishop was feted there this year, and the Knopf Poetry Series was launched there in 1980. “It’s just a magical place, one that feels personally important to so many of us.”

Founded in 1920 by Frances Steloff, Gotham became a literary oasis for authors and publishing figures, some of whom got their start working there. According to a story in the New York Times by Herbert Mitgang, Allen Ginsberg and LeRoi Jones (Amiri Baraka) worked there as clerks, but Tennessee Williams did not last a day. For one thing, “He didn’t know how to wrap packages.”

Man Ray, Arthur Miller, and W.H. Auden shopped there, and the Joyce Society has regularly held meetings there.

As Ms. Quinn said, Steloff “enshrined writers and served them . . . putting books with printings of 500 or even fewer in the window, stocking the rear room with hundreds of literary journals, hosting parties for little-known poets, scouting volumes desired by Marianne Moore and delivering them to her door, obtaining garden utensils for Henry Moore when he didn’t have the money to buy them.” Upon receiving the Presidential Medal of Freedom in 1976, Martha Graham thanked Steloff for signing a co-note for $1,000 that enabled her to start her dance company.

“The photographs on the walls tell the story of 20th-century American literature as no other walls in New York that I know,” Ms. Quinn said. Mr. Brown, a bibliographer and book appraiser, bought Gotham from Steloff in 1967.

“I can’t believe this place is closed,” an attorney based in Fort Lauderdale, Scott Weiss, said. He had walked in the rain on Friday to reach the store, only to read the sign that said, “Be Back Soon.” Mr. Weiss collects materials relating to Salvador Dalí. He has bought three copies of exhibition catalogs for Dalí at Gotham and has never seen them for sale anywhere else. He praised the store as a place where one can discover items at a reasonable price.

The last decade saw closings of independent bookstores such as Eeyore’s (1993), Shakespeare and Company on the Upper West Side (1996), and Books and Company (1997). Not far from Gotham, Scribner’s, Doubleday, and Brentano’s disappeared in the 1980s and 1990s. A Barnes and Noble on the corner of 46th and Fifth Avenue stands about a block away from the present site of Gotham.

In August 2004, Gotham moved a block south from its previous location, 41 West 47 Street, in the heart of the diamond district, to its current location, a larger space at what was formerly the antiquarian bookstore, H.P. Kraus. When the previous location went on the market, Woody Allen expressed interest in the “Wise Men Fish Here” sign, according to the Web site Goreyography.com.