The world's top five security software vendors, including Symantec and Trend Micro, lost significant market share between 2006 and 2010, according to research firm Gartner.
In 2010, security firms Symantec, McAfee, Trend Micro, and the security arms of IBM and CA Technologies between them accounted for just 44.3 per cent of the market, down significantly from 60 per cent in 2006.
The drop can be largely attributed to new, agile players moving into the market, according to Gartner.
Ruggero Contu, principal research analyst at Gartner, said: "The information security market is in a continuous state of consolidation, but even fairly intense merger and acquisition activity has not stopped these smaller companies from having an impact.
"These companies bring innovative technology solutions to cater for end-user requirements created by new threats, often introduced by cyber criminals taking advantage of vulnerabilities that come from changes to IT ecosystems."
Contu added that he expected the security market to remain dynamic, with further consolidation unlikely given the flood of security threats driving the need for innovation.
"The security market continues to provide good growth opportunities for both established players and startup companies, and the landscape remains dynamic with many competitors in the fray," said Contu.