Autodesk no longer sells perpetual licenses, but they do sell "legacy maintenance" spots. If you find a reseller selling a 2020 "perpetual license transfer," you can legally own a permanently activated copy. Expect to pay between $4,000 and $6,000 for this rare license.
Verification: Once done, go to Help > About > Product Information. It should read: "Autodesk Navisworks Manage 2020 – Licensed" with no expiration date if you bought a perpetual transfer, or a valid end date for subscriptions. autodesk navisworks manage 2020 full activated
If your company never upgraded from a perpetual license purchased before 2016, and you kept it on a maintenance plan, you can still activate Navisworks 2020 offline using the legacy product key (691K1). Autodesk no longer sells perpetual licenses, but they