Norton Simon on List of Bogus Rembrandts : Art: Panel of experts, in third of five reports, says about 50 paintings by the Dutch master were really the work of others.

A research panel says about 50 paintings attributed to 17th-Century Dutch master Rembrandt van Rijn are works of other artists--including a 1636 portrait in the collection of the Norton Simon Museum in Pasadena.

The Norton Simon Museum acquired the portrait, which the panel attributes to Rembrandt contemporary Carel Fabritius, for about $3.8 million in 1969. If sold as a genuine Rembrandt, the painting would probably bring more than $10 million today. But as the work of Fabritius, who is known as a Rembrandt imitator, the painting’s value would drop to about one-tenth of that.

But the Simon museum rejects the panel’s assessment of its painting and has no plans to change the attribution, according to Vickie Rogers, director of program planning. “We do not endorse the methods of the Rembrandt Research Group. Rembrandt attributions have been debated for 300 years, and this is just the latest chapter in that discussion. History will decide,” Rogers said.

The portrait will remain on view along with the museum’s two other Rembrandt paintings, “Titus” and “Picture of a Bearded Man in Wide-brimmed Hat,” Rogers said.

The Rembrandt Research Group, which is looking at all 500 to 600 works attributed to the artist, published its third of five volumes today. Of 100 paintings examined in Volume 3, “about 50% are not genuine Rembrandts,” said panel member Jozua Bruin. Also questioned was the 1635 “Landscape with Carriage,” owned by the Wallace Collection in London.

“The outcome of Volume 3 reflects the 50% score in the first two volumes,” Bruin said. In those volumes, roughly 100 paintings were branded as wrongly attributed to Rembrandt.

The third volume, in which Rembrandt’s monumental “Night Watch” has gotten the stamp of approval, was published today. The first and second volumes were published in 1982 and 1986 respectively.

Most of the falsely attributed works probably were painted by Rembrandt students or paid assistants in his workshop, according to Bruin.

The panel, which is subsidized by the Dutch government, began its work 21 years ago. It scrutinizes each work with a close analysis of the paint, the cloth or wood on which it is painted, and ultimately, the painting style, according to Bruin.