Hello everyone!
I sent Pavel a message asking him for a permission to use his design for commercial purposes. He has no objections on using the mask for any purposes, including commercial production. As for royalties, he leaves that to producers

If you think you can and want - feel free to do so. His only condition is that you have to mention that the mask was invented by him. "Bahtinov Mask" sounds good, and it is also widely used in Russian speaking forums.

John, I also asked him about your e-mail. He said that it was lost in his Spam folder. Seems like he found it now.