April 25 (Bloomberg) -- Shares of Akamai Technologies Inc., whose software speeds the delivery of Internet data, dropped the most in 3 1/2 years after first-quarter profit fell short of some analysts' predictions.

The shares slid $6.24 to $48.35 and declined as much as 13 percent in extended trading, the most since October 2003. They fell $5.62 to $48.97 at 4:01 p.m. New York time in Nasdaq Stock Market trading.

Profit had exceeded analysts' estimate for five straight quarters before today's report. Excluding some costs, profit in the three months ended March 31 met the 28-cent average estimate of 13 analysts surveyed by Bloomberg. Sales exceeded analysts' $138.8 million average projection.

``This was slightly disappointing relative to their ability to beat for several quarters in a row,'' said Brent Bracelin, an analyst at Pacific Crest Securities Inc. in Portland, Oregon, who rates the shares ``outperform'' and doesn't own them. ``Expectations were very high going in.''

Net income increased 67 percent to $19.2 million, or 11 cents a share, from $11.5 million, or 7 cents, a year earlier, the Cambridge, Massachusetts-based company said today in a statement. Sales rose 53 percent to $139.3 million from $90.8 million after customers upgraded Web sites to carry more video.

The company expects second-quarter sales of $149 million to $153 million, Chief Financial Officer J. Donald Sherman said today on a conference call. That compares with sales of $100.6 million a year earlier. Earnings excluding some costs will be 29 cents to 30 cents, up from 20 cents.

Estimates

Analysts project 31 cents, the average of 12 estimates in a Bloomberg survey, on sales of $150.3 million.

Previous quarters in which the company surpassed forecasts may have fostered unrealistic expectations for some investors, Chief Executive Officer Paul Sagan said on the call.

``Some people may have gotten comfortable that we kept beating the guidance and thought that's just the way the world works,'' Sagan said.

Akamai faces increasing competition from companies including Limelight Networks Inc. of Tempe, Arizona, Bracelin said. Limelight filed for an initial public stock offering on March 22. The company had a loss of $3.7 million in 2006 on sales that tripled to $64.3 million.

Other rivals include Level 3 Communications Inc. of Broomfield, Colorado, and Internap Network Services Corp. of Atlanta.

``People are going to be a little more concerned about new competitors,'' Bracelin said.

(Akamai held a conference call to discuss results. To listen to a replay, call 1-800-642-1687, passcode 3310990.)

To contact the reporter on this story: Michael White in Los Angeles at Mwhite8@bloomberg.net

Last Updated: April 25, 2007 18:37 EDT