The Toshiba site says about their HDDs: "If you bought the device separately from a shop, then claims can only be made with the shop that sold you the drive. "
Also "Toshiba does NOT provide a direct repair service to anyone other than our direct customers. It is not possible to make claims directly to Toshiba in cases of possible defects. Therefore please do NOT send a defective drive to Toshiba, because Toshiba cannot process this type of transaction. "
I find it hard to believe any major company would impose terms like this. I looked around for some mitigating clauses but so far haven't found any.