Yamada is Honda’s primary pump supplier, I think they also supply Subaru and Nissan(though Nissan is mostly Hitachi, you can see either the Hitachi or UJ for Unisia Jecs, who is part of the former). Aisin does some Honda business. from what I see on Rock, the Honda D-series pump is made by Aisin in Japan but it looks totally different than the OE Yamada from the US, and it’s an “original” casting, no grind marks like the Toyota pumps.Yup, the pump I recently bought from the Honda dealer was made by Yamada.