Sotheby's reported a third-quarter net loss of $11.2 million, or 20 cents per share, before factoring in a $15.2 million charge for the expansion of its auction facility in New York. The loss was in line with Wall Street expectations, and compared with a loss of $9.2 million, or 16 cents per share a year earlier,

When the expansion-related charge in 1998 and a non-recurring $3.5 million charge a year ago are included, Sotheby's third-quarter net loss deepened to $20.8 million, or 37 cents per diluted share, from $11.3 million, or 20 cents per diluted share.

The company, which conducts auction, art-related financing and real estate activities, said its third quarter is typically a period of sluggish sales activity in the art auction market and it historically reportsa loss in the period. The company said the third quarter in 1997 reflected only 8 per cent of its auction sales for that year.

Sotheby's said its 1998 third-quarter revenues were flat at $51.3 million. The company said ongoing investments in expertise and new initiatives offset a 13 per cent increase in revenues in the first nine months from a year earlier.

The company also said next week it will hold the strongest series of Impressionist, Modern and Contemporary art since 1990, including the auction of works form the storied corporate collection of the Reader's Digest Association Inc.

The third quarter 1998 results matched analysts consensus estimates, according to First Call Corp, which tracks such estimates.