Its seal consisted of two intersecting squares with the first character of the owner's surname in the middle, and its size indicates that there were usually two people working in it at any given time.
書店「文海堂」，店主為吉文字屋歌助，兩個相疊的正方形內加上一個「吉」字則是該店店印。從該店的規模看來，平時的看店人數應為兩人。