Amazon's spat with publishing conglomerate Hachette has been unofficial but well-documented, as the retail giant uses its considerable muscle to gain more favorable terms in a deal with one of its largest book partners. On Tuesday it swung its biggest hammer yet, saying formally that it's buying less inventory from Hachette and is no longer taking pre-orders on its books. That means that while you can still buy a Hachette book on Amazon, you can't do so ahead of its publication date, and the company will only buy the book from Hachette when you buy it from Amazon. That means slow shipping and no cheaper prices — none of the perks of being an Amazon supplier or customer.

In some ways the move is just a formalizing of what Amazon has been doing for weeks as it has negotiated with Hachette, primarily over the price of ebooks. In a note in its forums, the company compares itself to a bookstore, saying that while it wouldn't cease sales of Hachette books, it has every right to essentially deter them. "A retailer can feature a supplier's items in its advertising and promotional circulars, "stack it high" in the front of the store, keep small quantities on hand in the back aisle, or not carry the item at all, and bookstores and other retailers do these every day." The note goes so far as to recommend that buyers look for Hachette books among its third-party sellers, or even buy from one of Amazon's competitors.

"We regret the inconvenience and encourage you to purchase from one of our third-party sellers or from one of our competitors."

In an ever-changing, increasingly digital books market, everyone wants their cut. And Amazon's in a uniquely powerful place to make sure its own never gets smaller, a position it's making clear to Hachette in no uncertain terms. Amazon says it's still working with Hachette to come to a resolution, but lands on a deeply pessimistic note: "we are not optimistic that this will be resolved soon."