The panel has agreed to reveal, on a case-by-case basis, why it rejects works, but the process is still far from transparent

A Sotheby’s lawyer describes the work of its provenance research team

Art Basel '04 fair report

Pierre Valentin suggests that the decisions of expert committees should not be beyond the reach of the law

The board acknowledges that the artist “employed assistants”, but says that he “carefully supervised them”

The panel has attracted controversy for refusing to authenticate works attributed by their owners to Warhol

Ada Berkowitz, New York

Four people are responsible for establishing whether works by the artist are authentic. Their decision is final. Now they are under attack by collectors who say they have ulterior motives for rejecting works

Dr Kenneth Wayne says scholarship is the way forward

Prices are rocketing, but perhaps not everything is right in this field with many experts questioning the authenticity of some pieces

This will assist in the identification of looted artworks

With a Calder, the judge overruled the expert; with a Schiele, the judge decided deceit was the clincher, and with a Braque, the judge upheld Christie’s right to fear liability

“My grandfather copied his own works”

The Calder foundation cites fears concerning authenticity

London artists Tracey Emin, Gary Hume and Gillian Wearing play bit-parts

“Sunflowers” back in bloom

Amidst arrests regarding contraband and fake art importing

The case is particularly difficult given the scarcity of drawings by the artist

New revelations point fingers at the artist, but the question of whether they were forgeries or merely innocent copies remains

In deciding that the certificate of the artist’s heir is no longer sufficient to prove a work’s authenticity, French courts will require auctioneers to be more thorough in future

The Andy Warhol Foundation is appealing the case, which will be heard in October

Leading expert queries items in exhibition, all of which come from private collections

The owner's careless sales technique led the carabinieri right to his doorstep

The show will proceed to to the Guggenheim despite confusion arising from a lack of transparent communication between Russian and US committee members

Raphael’s “Madonna of the Pinks” has now been firmly reattributed after cleaning

The looted manuscript has now been fully reproduced and described