We get asked to clone voices we will not clone. Sometimes it is a celebrity for an advert. Sometimes it is a former employee whose recordings the company still owns. Occasionally it is a deceased founder, which is the request that makes everyone in the room go quiet.
The technical capability is not the constraint any more. Thirty minutes of clean audio produces a voice most listeners cannot distinguish from the original. The constraint is whether you had the right to do it, and that question is answered by evidence rather than by intent.
Our rule is narrow and inflexible: a documented, informed consent from the identified speaker, covering the commercial use intended, recorded against the voice and retained for its life. No consent, no voice.
"We own the recordings" is not consent. Owning a recording of someone's voice gives you rights in that recording, not the right to generate new speech they never said. Those are different things, and conflating them is how organisations end up in a dispute they cannot win.
"They're an employee" is not consent either. Employment does not imply permission to synthesise someone's voice, and consent obtained under the implicit pressure of a job is exactly the kind that does not hold up.
"They're deceased" is the hardest one, because there is often genuine affection behind the request. It is also where we are most firm, because the person most affected cannot object. We decline these.
This costs us business, and we have thought carefully about whether we are being precious. We are not. Synthetic voice is the single most abusable capability we ship. The reputational and legal exposure of getting it wrong once outweighs the revenue from getting it right a hundred times, and more importantly, a person whose voice is used without permission has been wronged in a way that a refund does not fix.
If you need a distinctive brand voice and consent is difficult, there is a straightforward alternative: cast a voice actor, get consent as part of the engagement, and clone that. It is cheaper than the alternative in every sense.