Was that "sold by / ships from Amazon" or was it from a 3rd party vendor selling on Amazon Marketplace? I'd assume the latter.
3rd party fulfilled by Amazon. Shouldn't matter. Amazon put their name on the sale, the price was the normal price - which is overpriced for a battery, Amazon charged me, and Amazon refunded the money.
You can check the hologram on the package, etc., but some have reported getting counterfeit batteries in re-sealed OEM packaging. Counterfeiters are clever. If the 'ok price' is a good deal, it's almost certainly in the 'too good to be true' category...
Packaging was perfect. Correct hologram and all. Didn't notice anything was wrong until I actually held the battery in my hand.