Use This Terminal Command Before Selling a MacBook Pro with Touch Bar
Before you sell or give away a MacBook Pro with Touch Bar (which has a Touch ID sensor), Apple recommends that you boot the Mac into macOS Recovery and execute this Terminal command: xartutil --erase-all. We’re not entirely sure what it does, and Apple doesn’t offer any explanations, but we suspect it acts to clear the Secure Enclave that stores your fingerprint data. Regardless, it would be wise to follow Apple’s advice.