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1) A certificate giving the buyer the right, but not the obligation, to buy a specified amount of an asset at a certain price over a specified period of time. Warrants differ from options only in that they are usually listed.
2) A document of possession, issued by the warehouse company, for each lot of London Metal Exchange (LME)-approved metal held within an LME-approved facility. Warrants are used as the means of delivering metal under LME contracts.
* see also London Metal Exchange (LME)