When Adblock Plus said it had been "disinvited" from this week's Interactive Advertising Bureau's Leadership Summit, it raised virtual eyebrows across the Web. Wasting little time and mincing no words, the IAB's leader kicked off the event by firing back.

"Now, you may be aware of a kerfuffle that began about 10 days ago when an unethical, immoral, mendacious coven of techie wannabes at a for-profit German company called AdBlock-Plus took to the digisphere to complain over and over that IAB had 'disinvited' them to this convention," CEO Randall Rothenberg told the audience in his opening keynote Monday. "That, of course, is as much a lie as the others they routinely try to tell the world."

Adblock Plus, a software company that lets consumers block digital promos, had touted its willingness to speak with its adversaries, holding a self-styled "Camp David" meeting late last year with major publishers. And it seemed to feel shunned when the IAB refunded its conference registration fee.

Rothenberg blasted Adblock Plus' depiction of the situation and called the group "an unethical, immoral, mendacious coven of techie wannabes."

"We had never invited them in the first place," he said in his keynote. "They registered for this event online. When we found out, we canceled the registration and reversed their credit card billing."

Eyeo GmbH-owned Adblock Plus' ticket was pulled, Rothenberg said, "for the simple reason that they are stealing from publishers, subverting freedom of the press, operating a business model predicated on censorship of content and ultimately forcing consumers to pay more money for less—and less diverse—information. AdBlock Plus claims it wants to engage in dialogue. But its form of dialogue is an incessant monologue."

The IAB head went on to say that two publishers showed up at Adblock Plus' Camp David several weeks ago, but execs from those companies told Rothenberg that the software maker wasn't addressing the publishers' serious concerns. (Adweek reported back then that Jed Hartman, The Washington Post's chief revenue officer, was one publishing player who planned to attend.)

"Of course, none of this surprises me," Rothenberg said. "This is what happens when your only motivation, your only metric, is money. For that is what AdBlock Plus is: an old-fashioned extortion racket, gussied up in the flowery but false language of contemporary consumerism."

Publishers have been wary of AdBlock Plus' plan to grow an "Acceptable Ads" platform, which would let brands get around ad blocking if their promos met certain criteria and paid a submission fee. But it's not the only player trying to accomplish this goal, Rothenberg noted, while also naming startups such as Brave and Shine.

"But in fact, they are engaged in the techniques of The Big Lie," he said, "declaring themselves the friends of those whose livelihoods they would destroy, and allies to those whose freedoms they would subvert."

The IAB published the full text to Rothenberg's speech, which totals roughly 3,600 words and can be found here.

The drama between ad blockers and the IAB has been ongoing as of late.

On Oct. 15, the IAB seemed to pivot from its defiant position against ad blockers when Scott Cunningham, senior vp of technology and ad operations at the org, said the industry group should take some blame for the popularity of ad blockers. Cunningham explained that the IAB could have done a better job guiding publishers away from overloading consumers' Web pages and smartphones with data-draining ads.

"We messed up," he said. "Looking back now, our scraping of dimes may have cost us dollars in consumer loyalty."

Meanwhile, the IAB Leadership Summit is being held in Palm Desert, Calif., though many marketers were unable to attend due to the blizzard conditions that shut down the East Coast over the weekend.