The firm has built the facility into its Factiva Insight: Reputation Intelligence service, which previously only monitored mainstream media.
However, as the result of an agreement with Intelliseek, which specialises in analysing consumer media, it can now track more than 11,000 websites, and more than 4m of the most active blogs and message boards.
Factiva's move acknowledges the increasing influence that bloggers are having on companies and their brands.
Alan Scott, chief marketing officer of Factiva, said: "There are millions of blogs and message boards worldwide and any one of them can affect your organisation or brand."
Scott said that the sheer volume of information makes it impossible to read and analyse its impact on your business.
"Until now. Factiva Insight: Reputation Intelligence provides the sophisticated tools to sift through millions of pages of information and visualise potential threats, as well as hard-to-spot opportunities," he said.
It can tap into more than 9,000 media sources, including Dow Jones, Reuters and The Wall Street Journal, as well as websites. The information can be analysed by a company alongside its share price, sales revenues and other data.
Factiva is jointly owned by Dow Jones and Reuters.
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