That voice is owned by Apple, if you're on a Mac and it's one of the default voices. According to their EULA, they are for personal, non-commercial use while using MacOS only:
Voices Subject to the terms and conditions of this License, you may use the system voices included in the Apple Software (“System Voices”)
while running the Apple Software and (ii) to create your own original content and projects for your personal, non-commercial use. No other use of the System Voices is permitted by this License, including but not limited to the use, reproduction, display, performance, recording, publishing or redistribution of any of the System Voices in a profit, non-profit, public sharing or commercial context.
Unfortunately, I don't know who you might contact at Apple to license that voice for use. There are several companies that sell licensed voices including Cepstral https://www.cepstral.com and NeoSpeech NeoSpeech: Text-to-Speech (TTS) Software https://neospeech.com/