So I'm seeing Tesoro units put up for sell on Find's for sale forum and others that are used but seller claims that they have not sent in the warranty card. First let me say how wrong I feel that is. In speaking to my brother who is an attorney the seller is misrepresenting it and it is FRAUD. Doesn't matter if you send the card in or not. You are the original owner not the guy who is buying it. If you hold the card to give to the next buyer it is your intent to defraud Tesoro and other MFG. that require this to be done. Most require it to be sent in a short time after purchase or its invalid. While I'm sure it isn't something that would be economical feasible to pursue this in a court the person that buys this can be subject to have pay for their MD repair that they were told by seller that would not happen because they sent in the card. Wondering if when a MD is sold the dealer sends in a serial number of the unit when sold. If you want to support the Mfg. of the products be straight up and not cheat them out of service money needed to stay in business. Buyer Beware.