Some of the top publishers in the world are going to be investigated for possible antitrust violations in connection with the sale of e-books in the European Union.

According to an EU press release, Hachette Livre, Harper Collins, Simon & Schuster, Penguin and Verlagsgruppe Georg von Holzbrinck may have – “possibly with the help of Apple (News - Alert)” – taken part in “anti-competitive practices.”

The European Commission will look at whether there was any restricted competition in the EU because of the actions of the companies.

“The Commission will in particular investigate whether these publishing groups and Apple have engaged in illegal agreements or practices that would have the object or the effect of restricting competition in the EU or in the EEA,” according to the EC statement. The EC prohibits cartels and restrictive business practices.

The UK Office of Fair Trading concluded its related inquiry on Tuesday, passing the investigation over to the EC, according to The New York Times.

The EU inquiry developed after the EC inspected several companies involved with e-books. One question that arose is whether there was price fixing of e-books, according to Mashable.

In a related matter, MacObserver notes that Apple employs iBookstore “to sell and distribute ebooks to iPhone (News - Alert), iPad and iPod touch owners through the iBooks app.”

In a statement, Pearson, which owns Penguin, said it did “not believe it has breached any laws, and will continue to fully and openly cooperate with the commission,” according to a report from The Times. HarperCollins said that it was “cooperating fully with the investigation,” The Times adds.

In a related matter, Hagens Berman, a law firm, filed a class action lawsuit in California federal court in August claiming that “publishers and Apple increased prices for popular e-book titles to improve profits and force e-book rival Amazon to abandon ‘pro-consumer discount pricing,’” The Times said.

In other news about antitrust issues in Europe, European regulators closed an antitrust inquiry regarding IBM (News - Alert), earlier this year, TMCnet said.