Kershaw offers a Limited Lifetime Warranty covering the original owner against defects in materials and construction for the life of the product. It is explicitly non-transferable, and it excludes normal wear, rust, improper use or maintenance, accidents, loss and theft.
The non-transferable clause is the detail that catches people out. If you buy a Kershaw secondhand, or receive one as a gift where the giver bought it, coverage may not follow the knife.
This differs from Gerber, which extends coverage to the original purchaser or giftee. Read each brand's wording rather than assuming they are the same.
Rust is explicitly excluded, which is worth knowing on any steel that is not highly corrosion resistant. So is damage from improper use or maintenance, which covers most self-inflicted problems.
Loss and theft are excluded, as they are everywhere.
Claims go to Kershaw. See how to file a Kershaw warranty claim.
Warranty terms are set by the manufacturer and can change. The maker's own warranty page, linked below, is the authority. We repeat what it says; we do not extend it, and a retailer cannot promise coverage a manufacturer has not offered.