Sotheby’s lost $22.3m from January to March 2013, more than twice the amount for the same period in 2012.
However, this was chiefly because of new investment and increased operating costs resulting from a rise in the average value of lots sold, say the company.
In the first quarter, there was a 35% increase in the total sale price of lots sold over $1m, where auction commission margin experiences the most pressure.
The first quarter, generally a period of slow activity, is traditionally loss-making, and with overall revenues dropping by only 3% to $101.7m the performance appears relatively stable.
The restructuring of the buyer's premium in mid March, aimed at improving yields, has yet to have a significant impact on the bottom line.
"For over 98% of lots sold, this change represents an increase of 2% or less in the final purchase price and for all lots, a maximum 3.6% increase in the final purchase price," said a spokesman.
Chief executive Bill Ruprecht talked about the company "moving ahead with initiatives that expand our global relevance and reach: redefining and personalising the client experience at Sotheby's", possibly a reference to plans for further development of private sales with the opening of a gallery behind their Bond Street headquarters, in George Street, London.
"We have historically adapted to a changing world. We are still an auction house, but today we are also much more," added Mr Ruprecht.
Sotheby's are also placing even more emphasis now on web development so "our clients can engage with us anywhere, at any time on any device".