Indicators of bootleg DVDs:
1. Check their other items for sale. Small sellers (with a few hundred feedback) are selling everything new. You have to wonder where they get their inventories. Stealing from big box stores? That is a crime. Counterfeiting? That is also a crime. Ebay is essentially online yard sales for small sellers. Have you been to a yard sale of new stuffs only? As a rule, small sellers do not sell everything new. Also as a rule, licensed DVD sellers do not only have dozens of listings.
2. Read their negative ratings. Very likely you see reports on counterfeiting. They have to start over to have a new account when there are a few such reports. That is why their ratings are rarely over 1000.
3. If you cannot resist the low price and order from them, very likely the DVDs are shipped from overseas because that is where they are counterfeit. Buyers complained they still had not received the items after a few weeks. The discs skip or freeze, and the boxes are low quality. These over-glossy boxes are busted easily because the cheap glue does not last long. The first five seasons of this series have very unique boxes which is hard to counterfeit so it is easy to identify the fakes.
4. You may think you get a bargain but bootleg DVDs have no resale value while you can get much of your money back if you sell your authentic used ones.