I have created a custom font face for a client's logo, which is a registered trademark. For SEO reasons, the Logo is in a H1 tag at the top of the page. From an accessibility perspective, would it be acceptable to drop the '®' from the type and put the registered trademark logo in with another glyph? I.e. changing the S glyph to contain the registered trademark logo?
Is the client dead set for having the registered mark on the logo? There's a lot of brands that don't place it there at all. I feel it adds clutter to the logo personally and looks a lot cleaner without it.
If the client is persistent about letting the world know it exists, I'm not sure what advantages you gain by changing it to a glyph. Screen readers can read the ® as registered mark. I think you would lose that by trying to do a custom icon.
If you do place it on the logo, I'd make sure to add it after the full trademark. Current placement looks as though there's a trademark on the term Cook's.