A top-tier company: a leading firm with high reputation, strong brand, scale, good benefits, and stability.
彼は一流企業に就職してキャリアを積んだ。
He got a job at a top company and built his career there.
一流企業は福利厚生が充実していることが多い。
Top companies often have generous benefits.
新卒の学生は一流企業を目指して就職活動をする。
New graduates often aim for top companies during job hunting.