With its shares no longer in thrall to a post-IPO lockup,

Salesforce.com

(CRM) - Get Report

was off sharply Monday as investors moved quickly to lock in profits. In recent trading, shares of the business software vendor were off $1.02, or 6.3%, to $15.08 on volume that was more than 10 times average.

Salesforce went public in June, but as many as 89 million shares, most held by insiders, were not eligible to trade until Dec. 19, according to the company's registration statement. Although various restrictions make it impossible for all eligible shares to be sold at once, some analysts think that perhaps half that number will hit the market.

Today's selling, while heavy,

was not unexpected. "Salesforce.com investors have waited a long time for a liquidity event and many are likely to take this opportunity to lock in their gains," JMP Securities analyst Patrick Walravens said last month, as the end of the lockup loomed.

Salesforce.com ended its first day of trading -- June 23 -- at $17.10 and has traded as high as $22.70.