Included in the Buck warranty, it says it covers parts, that may or may not mean sheaths, usually with warranties the sheaths are not covered however and you're better off buying a new one, however if the sheath isn't any good, you may want to search for a suitable replacement. For example, I didn't like the way the Buck 119 sheath rattled so I searched the rack at Dicks and found a replacement in a ten dollar Winchester knife that happened to be about the same size as a 119 and fit it perfectly. If the sheath came messed up and it's only a couple of weeks old, I'm sure Buck would replace that for you, but sheaths, especially leather sheaths wear out very quickly with regular use so they are not generally covered unless there is a separate waranty listed, there is not for Buck so I'd have to assume that normal wear and tear on the sheath would not be covered. You would need to show the damaged one for a better answer than that, or just e-mail Buck, you'll usually get a response back within a day so it's probably worth while just to ask them. Also if I knew what kind of knife it was I could more than likely recommend a good replacement for it as I do it quite frequently.