Sotheby’s will sue a Chinese man who owes millions over non-payment for 20 works of art, The Wall Street Journal reports.

Zhang Bo, from mainland China, purchased 20 Chinese paintings in April, including a work of Xu Beihong worth $7.8 million Hong Kong dollars. Mr. Zhang’s total nonpayment amounts to 27.5 million Hong Kong dollars (US$3.5 million) plus interest.

The lawsuit filed in Hong Kong’s High Court indicated that Mr. Zhang was the successful bidder for the 20 works of art, for a total value of $34.1 million Hong Kong dollars (US$4.4m). Two owners of the works decided not to pursue legal action.

Sotheby’s told the Journal that nonpayments account for less than 2% of its total Asian sales in 2011, which amount to over US$1 billion. “Our lawsuits do not mean that we are experiencing more defaults than other auction houses. It just means that we take our obligations to our consignors seriously,” said a Sotheby’s spokesperson.