Mozilla vice president of business affairs and general counsel Harvey Anderson estimates that as a result of Microsoft's failure to include the so-called "browser choice" screen for Windows users in Europe for more than a year and a half, Mozilla lost between 6-9 million downloads in total.
In spite of ongoing legal action by the European Commission, Microsoft could face another lawsuit for loss of earnings, if Mozilla decides to bring the case to court.
Anderson explained on his blog that Mozilla saw Firefox daily downloads decrease by 63 percent to a low of just 20,000 a day just before the fix was implemented. Firefox downloads then increased by 150 percent to around 50,000 downloads a day after the Windows fix was issued to EU citizens in February 2010.
The "browser choice" screen allowed European users of Windows a choice of which Web browser to use on their machines. Browsers such as Firefox, Opera, or Chrome were offered alongside Microsoft's own Internet Explorer.
With the EU sending the statement of objections, the 27 member state bloc has formally charged Microsoft with antitrust offences following sufficient evidence to do so. Microsoft can either seek to settle the charges, which it will likely do, or battle it out for the long run, in which the software giant could face fines up to 10 percent of its annual turnover -- a maximum of €5.6 billion ($7.3bn).
After accounting for the aggregate impact on all the browser vendors, it seems like this technical glitch decreased downloads and diminished the effectiveness of the remedy ordered in the 2009 Commitments.
If we look at Net Applications' market share statistics, Mozilla has lost more than 3.6 percent in market share in the past 18 months alone, dropping from 23.72 percent from January 2011 when the browser choice was in place to just over 20 percent in the past quarter. The most noticeable drop was the month the browser choice screen was not included in Windows 7 (Service Pack 1) in February 2011.
Though Mozilla is registered as a non-profit organization, the firm requires financing and revenue to support development of the browser, along with the bevy of other applications and services the browser maker offers.
While Mozilla generates much of its income from financing and donations, the majority of its revenue is attributed to "royalties," including selling its products through various websites and through user search requests, according to its 2010 financial statement [PDF]. Mozilla said last year that the search contract with Google, which was set to expire in December 2011, was renewed for another three years, until 2014.
According to AllThingsD, Google will pay close to $300 million per year to include its search engine on Firefox's front page and to keep the search engine as the browser's default choice.
Ergo, the lesser the browser share, the greater the loss in revenue. If Microsoft is found to have broken its 2009 settlement commitments with the EU by failing to include the 'browser choice' screen since February 2011 -- which it likely will as it's admitted the mistake -- Mozilla could be allowed to bring a lawsuit citing loss of earnings.