Amazon CEO Jeff Bezos holds two Kindle Fire HD devices during a press conference on September 6, 2012 in Santa Monica, California. David McNew/Getty Images Amazon is facing fresh antitrust scrutiny after consumers filed a lawsuit Thursday accusing the company of illegally colluding with major book publishers to drive up prices for ebooks. The lawsuit claimed that Amazon negotiated anticompetitive deals in 2015 with the "big five" publishers — Hachette, HarperCollins, Macmillan, Penguin Random House, and Simon & Schuster — that allowed them to "inflate" prices by up to 30%. Amazon, which controlled nearly 90% of the ebook market as of 2018, was able to benefit immensely from the higher prices by charging consumers more, according to the lawsuit. Apple was found guilty in 2013 of colluding with the same five publishers — using a similar pricing practice — to illegally fix ebook prices, and lawmakers in the US and EU have previously criticized Amazon's alleged use of the so-called "most favored nations" clauses. Visit Business Insider's homepage for more stories. Several ebook customers on Thursday filed a lawsuit against Amazon accusing it of violating antitrust laws by illegally colluding with the "big five" publishing houses to drive up the prices of ebooks.The lawsuit alleged that Amazon entered into anticompetitive pricing agreements in 2015 with Hachette, HarperCollins, Macmillan, Penguin Random House, and Simon & Schuster that allowed the companies to artificially increase prices by as much as 30%.Amazon, which controlled 89% of the ebook market as of 2018, according to a Bloomberg analysis cited in the suit, then used its dominance to benefit from those prices hikes by charging consumers more."Time and again, Amazon's response to competition is not to compete on a level playing field, but to try to eliminate the competition - and that's not how things are supposed to work," Steve Berman, managing partner of Hagens Berman, the law firm that brought the suit, told Business Insider in a press release.Amazon and Hachette declined to comment.