After over two months waiting, I got a reply from Canson today.
Canson: although their papers do not contain animal derivatives with the exception of Mi Teintes and Ingres Vidalon, they do not now about the glue and packaging and several dyes get tested on rabbits.
So Canson is neither completely vegan nor is it cruelty-free.
The reply came from Lyra, so I guess it is the German distributor of Canson. And it is funny that the Canson response came via Lyra, but my inquiry to Lyra about their brand’s products was politely overlooked. But if Canson and Lyra are from the same company, Lyra is probably not vegan friendly as well.
Source: Mail contact