Amazon has found another battleground in its battle with publishers of eBook prices, or at least various states will be waging their own little wars against publishers, sorta, via state sales tax. Amazon classifies publishers that set their own eBook prices as merchants selling through Amazon, meaning they are subject to the sales tax in whatever state they report in, meaning Amazon will have to charge tax on top of whatever price the publisher sets for the eBook.

As TechFlash points out, Amazon posted a little note about this to the Kindle Community board on April 6.

Here’s the complete text of that note: Several publishers have recently changed the nature of their relationship with Amazon, moving to a business model whereby the publisher, not Amazon, is the seller of record for their books. Kindle books sold under this model are subject to sales tax based on the publisher’s state tax reporting obligations and the taxability of digital books in those states. Books where the publisher is the seller of record say “This price was set by the publisher.” Nothing has changed with respect to sales taxes on Kindle books where Amazon is the seller of record.”

If Amazon sets the price and acts as the merchant, it can deal with the taxes itself, eating the tax on $9.99 if it wants to. But if publishers set their own price, Amazon has to charge tax, meaning those more-expensive eBooks are going to be even more expensive.