Heirs of George Costakis, Naum Gabo and leading scholars disputed provenance claims of works on show at the Museum voor Schone Kunsten

Russian brothers behind the replicas are planning a show of their Leonardo reproductions next year

Dalloul Art Foundation investigates authenticity of some Middle Eastern works before museum opening

Ten cases were brought to court by collectors who purchased fakes through the gallery

Man recently imprisoned for similar scheme is among group accused of deceiving dozens of collectors around the world

The case against Oliver Wick was brought by the casino billionaire Frank Fertitta

Eric Spoutz was charged with selling fake works purportedly by De Kooning, Kline and Mitchell, that netted him $1.45m

The auction house has started proceedings in English High Court to recover its losses in the sale of a work that was deemed a forgery after technical testing

The Long Island dealer says she was abused and coerced into committing fraud by partner who fled to Spain

The artist himself has denied that the works investigated by police are fakes

US collector refunded by Sotheby’s after tests reveal modern materials in “Frans Hals” painting &nbsp;<br> <br>

Sotheby's refunds buyer of Frans Hals once owned by Giulano Ruffini

Collectors still in the dark even when experts have doubts as reports rarely published

Herrick Gallery is marketing two pastels and eight drawings said to be by the Irish-born artist

Old Master works by Orazio Gentileschi, Frans Hals and Diego Velázquez drawn into dispute

In a letter to a lawyer, Geng Jianyi calls his previous dismissal of the works as authentic a “failure of memory”

French court has reversed a decision fining the scholar for authenticating a fake work of art produced by Wolfgang Beltracchi

Collector John Howard bought the forgery from now defunct gallery for $4m

Convicted UK forger claims to have faked the Renaissance drawing

Yayoi Kusama and Random International are latest victims of China’s copycats

Eric Fischl among the artists to support authentication system launched in London this week

The gallery’s former director Ann Freedman will “tell her story”, her lawyer says

Clare Finn asks: What is forgery without the forgers?

Museum director and former antiquities minister refute Italian archaeologist’s theory

He is now suing former employees of the gallery