I bought a new monitor last year, and a few months later didn't know where I'd put the receipt. And I had never sent in the Warranty registration card in the box. In fact I rarely send in those cards anymore. Well, the receipt turned up a few weeks ago, and the monitor is working fine, but it makes me wonder, if I couldn't find a receipt, but had registered the purchase, would the manufacturer have a legal obligation to give me warranty service? And as I have the receipt, but had not registered the purchase, could the manufacturer legally or ethically refuse to honour the warranty service because the purchase had not been registered?