Grey market goods are legitimately manufactured items that are distributed by people other than the authorized wholesalers. Trademark owners are able to request that any grey market goods sold on eBay or other websites are removed; however, selling grey market goods is not technically illegal in many countries.
If you are caught selling grey market goods, you can face prosecution by the brand owner or account suspension if you are selling on a marketplace. If you are found to be importing grey market items, you may be prosecuted by your local customs authority.
You can protect yourself by familiarizing these frequently asked questions when importing to the US.