A, short for, is a published, unexamined Japanese patent application, in contrast to the kokoku or tokkyo kōhō, the examined and approved Japanese patent application.[1] Kōkai means "open to the public", or "laid-open". Kōkai are published eighteen months after the earliest priority date.
is another shorthand for kōkai tokkyo kōhō, taken from the first character of tokkyo (patent) and the second of kōkai.