A "trademarked term" is a word, phrase, or symbol that a company legally protects so that others cannot use it in a way that may cause confusion or falsely suggest an association with that company. Full definition
As far as I can determine, there is no obligation for a third party to so mark trademark terms, though it is commonly done. (law.stackexchange.com)
Honestly, it might be a little late for that: «Velcro» already occupies a shadow zone somewhere between «Linoleum» and «Kleenex,» two famous examples of trademarked terms, the first hopelessly lost to indiscriminate overuse, the second clinging to brand - name status (despite being what just about everyone calls the disposable tissue they sneeze into). (canadianbusiness.com)
GW had trademarked the term in relation to games only. (nocturnal-lives.com)