A sincere thanks to Le Mechanic for the post. It led me to question the 2 HG53"s bought off ebay late last year. One is still in the rather convincing packagong. The chains came with a quick link. I can't find any 9 speed quick links on the Shimano website. The quick link is packaged together with the chain. The chain has the following stampings: CN-HG53, Shimano, Taiwan, and on some outer plates KD with Taiwan above it.
I contacted the seller, cycle_bike1991, and asked if they could verify the authenticity of the chains. In their response they stated that they buy their quality chains from China and Malaysia (remember they are stamped Taiwan). That pretty much verified to me that these are counterfeit.
I tried the Shimano Anti Counterfeit Protection page on their website. The ACP verification app they talk about is not available in the Google and Apple app stores. I can't find any contact info to send an email or to call.
I turned to Ebay to report this and also can't find any contact info that works. If you open contact us it just leads to a page with more detailed subject info but no phone number or email. On my acccount page there is a "tell us what you think" button that leads to being able to leave a message but it is in reference to the account summary page. I left a message anyway but after sending a pop up said there would be no individual response but the info would be reviewed and used.
So left the buyer beware. And you're on your own. It doesn't look like anyone is too interested in policing it.