An opinion has it that since most of his peers who were vassals of Toyotomi were appointed Jugoinoge (Junior Fifth Rank, Lower Grade) at this time, this might be a written error of Jugoinoge rather than Shogoinoge.
なお豊臣家臣で一豊と同格の人物の多くは当時従五位下に叙せられているため、正五位下ではなく従五位下の誤記ではないかとの説もある。