US Patent 9213262 Developer supply container and developer supplying system

A developer supply container includes a developer accommodating portion for accommodating developer; a discharge opening for discharging the developer from said developer accommodating portion; a pump portion capable of changing an internal pressure of said developer accommodating portion so as to discharge the developer through said discharge opening; a venting portion for permitting venting between an inside and an outside of said developer accommodating portion while preventing flowing of the developer out of said developer accommodating portion; and a ventilation blocking portion for blocking venting of said venting portion at least when said pump portion operates.