If you find the maker of your knives on the list below then they are special Japanese knives and need to be sharpened as such....

Al Mar, Aritsugu, Artisan, Asai, Blazen, Brieto, Carter, Dojo, Fujitora, Fujiwara, Glestain, Global, Hattori, Hiromoto, Hirotomo, Hokiyama, Ishido, Itou, Ittosai, Kansui, Kasumi, Kikuichi, Kiya, Kobayashi, Korin, Kumagoro, Kumidori, MAC, Masamoto, Masanobo, Misono, Mizuno, Moritaka, Nenohi, Nenox, Ryusen, Sakon, Shigefusa, Shigeki, Shiki, Shun (Kershaw), Sugimoto, Suien, Suisin, Tadafusa, Takeda, Tanegashima, Togiharu, Tojiro, Tokifusa, Tosa, Watanabe, & Yoshikane