SAN FRANCISCO—Two Sol LeWitt wall drawings on temporary display at the San Francisco Museum of Modern Art were painted over on Wednesday, after eight years on view in the museum's atrium, the San Francisco Chronicle reports.

Wall Drawing #935 and Wall Drawing #936, both 29 by 32 feet, were commissioned by curator Gary Garrels on the occasion of a LeWitt retrospective at the museum in 1999. According to Garrels, they were not meant to stay up as long as they did.

In coincidental timing, they have been painted over just as Garrels has returned to SFMOMA after five years at the Museum of Modern Art in New York and three at L.A.'s Hammer Museum.

Despite being gone for now, SFMOMA owns the works, thanks to a late benefactor, Phyllis Wattis, who bought them in 2000 as a going-away gift for Garrels. In fact, the museum owns certificates of sole right of reproduction rather than the artworks themselves, which means the drawings can be recreated at any time as long as the recreations are to scale and follow the artist's written instructions.

"The art part of it is LeWitt's concept, and the concept is documented," said dealer Jeffrey Fraenkel, whose gallery works closely with the LeWitt estate. "No LeWitt drawings have been done by him. They have always been painted by his assistants."

The Chronicle quotes the late artist himself as once explaining, "The system is the work of art; the visual work of art is the proof of the system. The visual aspect can't be understood without understanding the system. It isn't what it looks like but what it is that is of basic importance."

The walls at SFMOMA will remain blank until next February, when Kerry James Marshall, the first recipient of the SFMOMA Atrium Commission, will paint them in correlation with his show opening that month at the museum.