The neutrality of Amazon has come into question after claims the retailer is pressurising publishers by fiddling with their product listings.
The New York Times reports that Amazon is currently in the midst of a contract dispute with book publisher Hachette and has as a result removed pre-order buttons, raised prices and increased shipping times for many of its titles.
It has also been accused of altering page designs to better promote Hachette's rivals.
Amazon has been criticised by many industries for the damaging effects its power creates, such as the strain put on independent book sellers. But until now everything it has done has been for the benefit of the consumer.
These new moves, however, degrade consumer experience for its own benefit and threaten to prove right critics who have warned of the dangers of monopolistic markets.
As NYT puts it: The more basic problem here is that Amazon is violating its own code. To win a corporate battle, Amazon is ruining its customer experience.”