Ai Weiwei

Artist Ai Weiwei at his Beijing office in April. (Ed Jones / AFP/Getty Images / May 9, 2012)

The ongoing tax case of Ai Weiwei has taken a significant step forward this week. The Chinese artist has told reporters that he will be allowed to challenge the legality of a $2.4-million tax bill in court.

Ai claims that the Beijing tax office violated the law in its handling of witnesses, evidence and more, according to reports. The artist's company was slapped with the bill after Ai was released after close to three months of secret detention in 2011.

Supporters of Ai believe that the tax bill is an attempt by the Chinese government to bully and intimidate the artist, who has been an outspoken advocate of free speech. It remains unclear when the case will be heard in court.

The decision appears to be a reversal of a March ruling that rejected Ai's appeal of the tax case.

On Wednesday, a Sotheby's auction in New York featured an edition of Ai's "Sunflower Seeds." The work, consisting of a ton of individually painted porcelain seeds, brought in $782,500. A much larger version of "Sunflower Seeds" was exhibited at the Tate Modern in London in 2010.

Ai has grown increasingly vocal in recent weeks in his provocations toward the Chinese government. In April, the artist streamed live webcam footage of himself to commemorate the one-year anniversary of his detention. He and his colleagues deactivated the cameras following demands by authorities in Beijing to halt the live stream.

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