prospective employer; company that has given an informal job offer
Refers to the company or organization from which a job seeker has received a 内定 (naitei, unofficial offer of employment). Common in Japanese job-hunting contexts.
I received official documents from my prospective employer.
He chose one company from among several that had given him informal offers.
Compound of 内定 (naitei, 'informal decision/offer') and 先 (saki, 'destination' or 'place'). The exact historical derivation is uncertain, but the word is a modern coinage reflecting Japanese recruitment practices.