The online ad industry has attacked Mozilla over its decision to block third-party cookies in a future release of Firefox, calling the move "dangerous and highly disturbing," and claiming that it will result in more ads shown to users.

The fierce reaction came from the Interactive Advertising Bureau (IAB) and Association of National Advertisers (ANA), both of which laid out positions in blog posts on March 14.

Dan Jaffe, the ANA's vice president of government relations, denied that it was a coordinated campaign, even though both the ANA and IAB blasted Mozilla on the same day and used many of the same arguments -- notably the threat to small businesses and a resulting curtailment of user choice on the Internet.

"The short answer is 'no' [it was not coordinated]. But all in the online ad industry are concerned about this ill-considered decision," said Jaffe in an interview. "This is damaging to consumer interest and will undermine the Internet."

In their blogs, the two groups lambasted Mozilla, predicting dire consequences, including the shuttering of small businesses and small websites, fewer choices for online users, and more ads in Firefox.

"If Mozilla follows through on its plan ... the disruption will disenfranchise every single Internet user," said Randall Rothenberg, president and CEO of the IAB, in his post. "All of us will lose the freedom to choose our own online experiences; we will lose the opportunity to monitor and protect our privacy; and we will lose the chance to benefit from independent sites ... because thousands of small businesses that make up the diversity of content and services online will be forced to close their doors."

Justin Brookman, director of consumer privacy at the Center for Democracy and Technology (CDT), a Washington, D.C.-based advocacy group. scoffed at some of Rothenberg's arguments. "This idea that blocking cookies is depriving users of choice rings hollow," Brookman said. "They talk about the small publishers, but it's small ad networks that they represent. [Even then], it's unclear how much small sites depend on behavioral advertising."

Although Firefox is not the world's most-used browser -- that distinction belongs to either Microsoft's Internet Explorer (IE) or Google's Chrome, depending on which measurement one uses -- it accounted for between 20.1% and 21.4% of browsers used last month on desktop and notebook computers.

What raised the IAB's and ANA's hackles was Mozilla's decision last month to automatically block all third-party tracking cookies in a future version of Firefox, perhaps as soon as June with the release of Firefox 22.

Cookies are used by online advertisers to track users' Web movements, then deliver targeted ads, a practice labeled "online behavioral advertising," or OBA, by the ad industry.

The new Firefox policy will allow cookies presented from domains that users actually visit -- dubbed a "first-party" site -- but will automatically block those generated by a third-party domain unless the user had previously visited the cookie's site-of-origin.

The result, argued Jaffe, will not be what people expect. "The facts are that [Firefox users] will get more ads, not less, and those ads will not be tailored to their interests," he said. "They'll see untargeted ads, which will look like spam. We have to get this information to them somehow."

Mozilla has not set a Firefox release for the third-party cookie blocking, but the earliest would be Firefox 22 in late June. That edition is slated to move out of the "Nightly" channel, the roughest-edged version aimed at developers, into Aurora on April 2.

But it could be pushed to a later Firefox, or never see daylight. "As with all our new Firefox features, there will be months of evaluating technical input from our users and the community before the new policy enters our Aurora, Beta and General release versions of Firefox," said Brendan Eich, Mozilla's CTO, in an email. "This will stay in our Nightly build until we are satisfied with the user experience."

The ad industry's assault on Mozilla was not its first volley against browser makers.

Since Microsoft unilaterally decided last year to switch on the "Do Not Track" (DNT) privacy feature in IE10 -- Windows 8's default browser, which is now being pushed to Windows 7 PCs -- the online ad industry has loudly condemned Redmond. In October, the ANA called Microsoft's DNT position "unacceptable."

Work by the Worldwide Web Consortium (W3C) to come up with a DNT standard has effectively stalled over Microsoft's move and other issues, although the standards-setting group continues to meet, most recently in Berlin.

Last year, Brookman had predicted that, failing a DNT agreement, browser makers would take matters into their own hands. And that's what they've done, he said in a February post about Mozilla's decision. "Given the continued lack of an agreement on a Do Not Track standard, we think [Mozilla] made the right call."

From the ad industry's perspective, Microsoft and Mozilla are guilty of the same crime: Making privacy decisions for users. "I'm astounded, frankly, that [Microsoft and Mozilla] essentially say, 'I'm smarter than you are, we will decide for you,'" said the ANA's Jaffe.

But both Mozilla and Brookman pointed out that Mozilla's Firefox plans are no different than what Apple's Safari browser already does. By default, Safari blocks third-party cookies, and has since its 2003 debut. The iOS version of Safari has done the same since its 2007 inception.

"They don't get that the Web works fine on Safari," Brookman said. "That's a tough story for them, that Safari users aren't complaining, that they're getting the content they want."

Mozilla acknowledged it was not breaking new ground when it announced the plan to bar third-party cookies. Eich repeated that in his email reply to Computerworld's questions. "Mozilla is not the first to propose this feature," Eich said. "For years, Apple's Safari browser has only accepted cookies from the websites users visit, which is the exact feature Mozilla is now testing."

When asked why the ad industry reacted to Mozilla's move, while it had been silent on Safari's identical practice, Jaffe only said that the ANA -- and by association, other advertising organizations -- has spoken out against all decisions it believes threaten ad-supported websites.

"Any group that stands between consumers and advertisers is misguided and unnecessary," said Jaffe. "We have made many statements making that clear. This isn't a fight between the industry and any specific entity, but a philosophical fight."

Computerworld, however, was not able to find any public statements by the ANA or the IAB taking Apple to task for Safari's by-default blocking of third-party cookies.

The industry's silence may have been based on the small share Safari has of the desktop browser market: Just 5.4% in February, according to metric company Net Applications' calculation.

But Safari is the dominant mobile browser, with a 55.4% share there last month. Net Applications data showed that mobile accounted for 13.2% of all browser usage in February, making Mobile Safari's contribution 7.3% ofall browsing. Add that to Safari on the desktop and Apple's browser's overall share, both on the desktop and on mobile, was 12%, or within shouting distance of Firefox's total of 17.3% (Mozilla has an almost-invisible share of just 0.01% on mobile).

By ignoring Safari on iOS, the ad industry shows shortsightedness, said Brookman. He had a point. In the last 12 months, mobile's share of all browser usage has almost doubled, climbing from 7.2% to 13.2%. At that pace, mobile browsing will account for 20% of the total by the end of April 2014.

In the end, Brookman saw the ad industry's censure of Mozilla as another example of its determination to stymie change and retain the status quo. "They do want to keep the status quo," Brookman said, adding that advertisers only want to concede the least possible.

Jaffe rejected that. "We have changed the status quo," he countered. "We have spent millions and years to create the program."

He was referring to a self-regulatory program, which includes an educational website and in-ad icons that when clicked let consumers opt-out of behavioral advertising, developed by the Digital Advertising Alliance (DAA), a collection of several ad industry organizations that includes the IAB and ANA.

Jaffe claimed that of the 18.5 million visitors to DAA's AboutAds website, only 1 million have used it to opt out of tracking, citing the figures to back up his contention that Internet users are not interested in tracking, surveys notwithstanding.

"The Internet was created on the foundations of advertising," said Jaffe. "There are true privacy concerns of the public, they're serious concerns and should be respected. We are having that conversation with consumers. But Mozilla is cutting off that conversation."

Not every advertiser agrees.

Last Friday, the Online Publishers Association (OPA), a group whose members include major online media outlets like Disney, ESPN, IDG -- Computerworld's parent company -- NBC, the New York Times and the Wall Street Journal, pooh-poohed the ANA's and IAB's portents.

"In spite of the doom-saying, Mozilla's move to block third-party cookies in the newest version of Firefox does not spell disaster for the advertising and publishing businesses," the OPA said. "If anything, it sheds more light on the need for an ecosystem-wide solution."

The OPA's members, of course, would be little harmed by Firefox's third-party cookie blocking, as they are large enough to sell their own ad inventory, and have little or no need to go to the third-party ad networks whose tracking would be impacted.

Brookman made much the same call as the OPA in his February blog post. Noting that the ad industry had promised the Obama administration it would participate in self-regulation, but that tracking had in the meantime ballooned, Brookman had hopes that Mozilla's move would nudge advertisers to "reach accommodation on a reasonable opt-out regime for third-party tracking," preferably through the W3C.

But if the industry doesn't, it's fighting a battle it cannot win.

"Browsers have a direct relationship with the user," Brookman observed. "On the other hand, ad networks' relationship with the user is intermediated by those same browsers, as well as publishers who are also increasingly worried about user trust."

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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