Mozilla and Google have struck a new search deal that will provide "significant revenue" to the maker of Firefox.
"We're pleased to announce that we have negotiated a significant and mutually beneficial revenue agreement with Google," Mozilla said today in a statement . "This new agreement extends our long-term search relationship with Google for at least three additional years."
Under the deal, Mozilla will continue to offer Google as the default search engine in Firefox, which now controls about a quarter of the browser market.
"Mozilla has been a valuable partner to Google over the years and we look forward to continuing this great partnership in the years to come," said Alan Eustace, Google's head of search.
Mozilla declined to provide details of the new contract, citing confidentiality requirements. Later, a spokesman refused to say whether the deal was comparable to the previous agreement.
In 2010, the last year for which Mozilla has released financial statements, the Google contract generated 84% of Mozilla's $123 million in revenues, or approximately $103 million.
Google's contribution to Mozilla's bottom line in 2009 was about $89 million, or 86% of the browser maker's annual income.
The Mozilla-Google deal expired last month, but Mozilla did not alter Firefox's default search provider or the browser's start page, which displays Google's search page.
Questions about Mozilla's dependence on Google have been raised since the latter launched its own Web browser, Chrome, in September 2008. According to Internet metrics firms StatCounter, in November 2011, Chrome owned a 25.7% share of the global browser usage market to edge into second place ahead of Firefox's 25.2%.
Last week a research testing company accused Google of attempting to quash Firefox using a triple-threat campaign to deny it revenues, withhold anti-malware services and -- through a Google-sponsored report -- claim that Chrome is significantly safer.
Google denied the second and third charges, and with the announcement today, has made the first moot.
Mozilla has made only minor steps to wean itself from Google. In October, the open-source organization launched a customized edition, dubbed "Firefox with Bing," that uses Microsoft's Bing search as the default engine.
As recently as two weeks ago, Mozilla declined to confirm that it had renewed the lucrative Google contract, saying then only that it was still negotiating with its browser rival.
Because of Mozilla's financial disclosure timetable, the impact of the new contract won't be apparent until the fall of 2013, when Mozilla issues revenue numbers for 2012.