Audinate does not offer a public, permanent "free license key." They are a publicly traded company (NASDAQ: AUDC) that relies on software sales for a significant portion of their revenue. However, there are nuances to this.
When you see websites promising "exclusive license keys" or "key generators" for Dante, proceed with extreme caution. Because Dante Virtual Soundcard requires an internet connection to activate against Audinate's central servers, "cracked" keys or shared serial numbers almost never work. Most sites offering these are actually delivery vectors for malware or phishing scams designed to exploit IT professionals and audio engineers. Legitimate Ways to Get DVS for Free (or Cheap) dante virtual soundcard free license key exclusive
What (mixer, interface, etc.) are you trying to connect to? Is this for a one-time event or a permanent studio setup ? Audinate does not offer a public, permanent "free