Shares of online auction operator Liquidity Services (LQDT) are advancing after the company reported that its gross sales summary, or GSS, increased 18% last month compared with the same period in 2012. WHAT'S NEW: The company, which provides marketplaces for surplus and salvage assets, reported that its GSS surged 18% year-over-year in March to $258M. The increase was in-line with the online retailer's guidance. ANALYST REACTION: In a note to clients, Robert W. Baird analyst Colin Sebastian wrote that Liquidity Services' growth excluding its acquisitions increased to 10% in March, compared with slightly negative growth in January and February. Although Liquidity Services is facing multiple headwinds, its long-term opportunity is still compelling, wrote Sebastian, who maintained an Outperform rating on the stock. TODAY'S PRICE ACTION: In mid-afternoon trading, Liquidity Services climbed $3.60, or 12.40%, to $33.