Yes. Böker Plus knives are covered by Böker's limited lifetime warranty on material and workmanship to the original owner, the same program that covers Böker and Böker Magnum. The line being manufactured internationally does not change the coverage.
Böker Plus is produced in China, Italy, Spain and the United States depending on the model. Regardless of where a given knife was built, it carries the Böker warranty program.
That is a deliberate choice by Böker and it means origin is a question about manufacturing, not about support.
Material and workmanship defects are covered. Normal wear, sharpening damage and misuse are not, which is the standard shape of a knife warranty.
Coverage runs to the original owner.
Böker USA, Inc. of Denver, Colorado handles the US market. Böker's service page, linked below, is the starting point.
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.