I recently purchased a Seagate external USB drive and enclosure as a unit. The retailer said it had a 5 year warranty. I doubted that right off the bat, because I had read on the Seagate site that only certain OEM drives purchased to install in a tower, or a tower pre-assembled with a Seagate drive had a five year warranty. The Seagate site describes the product as having a 12 month warranty.
After registering my new drive on the Seagate site, I then checked my warranty conditions by entering the model and SN. Fifteen months, from October 30 2006 to February 5, 2008 !
How they came up with that number I do not know. Anyways, 15 months is better than 12, so I am happy.
-Bob