The antivirus software business is big and it's only getting bigger.

Gartner numbers illustrate the market reaped $4 billion dollars worth of business in 2005, a 14 percent jump over the year before. Three vendors benefit the most from that growth, representing 86 percent of the market's revenues, but that's about to change.

Symantec accounts for nearly 54 percent share, a 12 percent revenue gain over 2004. Its next closest competitors are McAfee, which owns 19 percent of the market and earned 13 percent revenue growth, and Trend Micro, which represents 14 percent of the market on 9 percent revenue growth.

The fastest-growing antivirus vendor however is Panda Software, which grew its 2005 revenues by nearly 24 percent to a fourth-place overall finish with a 3 percent market share.

The real elephant in the room, however, may well be Microsoft.

The company is entering the antivirus market with both feet this year with the introduction of Windows Live OneCare and Microsoft Antigen among other security initiatives.

"We believe that Microsoft's entry into the antivirus market will have a huge long-term impact on the shape of the already commoditizing consumer desktop security markets," Nicole S. Latimer-Livingston, principal research analyst at Gartner, told internetnews.com.

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