It is Spanish as you say, but it is not a copyright. It refers to the trademark.
If you look at the logo on that same gun, you will see it says 'Trade' above and 'Mark' below, and the very bottom line says "Reg. U.S. Pat Off". The 'Marcas Registradas' merely restaes in Spanish that the trademark (logo) is registered.
S&W always had a strong market in Latin America. The Marcas was added in 1948 because of sales in that market.

__________________
Regards,
Lee Jarrett