Saying Mozilla was "caught in the middle," Hilwa argued that the company was reacting to pressure -- perhaps, as Valdes said, to a vocal minority -- because its users blame the browser, not necessarily advertisers, for privacy failures. "There is no doubt users will hold browsers accountable for any breaches of privacy or excesses of the advertising industry in siphoning data," said Hilwa. "[Browser makers] feel under pressure to control the type of data that can seep through their browsers."
The recent disclosures of widespread government surveillance has added fuel to that fire, Hilwa noted.
For its part, Mozilla declined to directly rebut Rothenberg's denunciations, and instead issued a statement that walked a line similar to what it has said before when it's butted against advertisers.
"Mozilla feels advertising is an important component to a healthy Internet ecosystem, and over the coming months we'll be working to address valid commercial concerns in our third-party cookie patch before advancing it to the general Firefox release," said a company spokesman, again intimating that the cookie-blocking plan was far in the future. "We'll continue gathering input while keeping the dialogue open with the hope that advertising industry groups will respect the choices users make to form the Web experience they want."
Mozilla, ironically, indirectly relies on advertising revenue for the vast bulk of its revenue. In 2011, the last year for which it reported financials, Mozilla earned $162 million, or 99% of all revenue, from deals with search engines, which pay the firm to make their services available to Firefox users.
Those deals are predicated on Firefox users clicking on ads within the ensuing search results.
Mozilla has been aggressively moving on to other projects, however, including Firefox OS, as a hedge against the decline of desktop browsing and a concurrent reduction in search-based revenue. But the desktop versions of Firefox, which until late 2009 were consistently gaining browser user share, have budged little over the last 12 months.
According to Web analytics firm Net Applications, Firefox on the desktop accounted for 19% of the browsers used worldwide during June. In mobile browsing, where Mozilla has devoted significant resources, not only to Firefox OS but also to an Android browser, Firefox held an almost-invisible 0.03% user share.
The IAB's members include Apple, Google, Microsoft and Opera -- four of the five top browser makers -- as well as the BBC, CBS and IDG, the parent company of Computerworld.
This article, Online ad group accuses Mozilla of anti-business bias, was originally published at Computerworld.com.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed . His email address is gkeizer@computerworld.com.
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