Life In 19x19

My wife got me a goban for Christmas. I'm guessing it's actually a shogi board (shogiban?), since it's 10x10 with the outer lines very close to the edge. I'm not familiar with Asian games besides Go, so that's just a guess.

(As an aside 10x10 hasn't felt all that different from a 9x9 game. I though the lack of middle lines might be jarring, but symmetry breaks so quickly in a go game anyways it doesn't seem to particularly matter).
Anyways, my question for those of you familiar with Japanese is "what's written on the back?"

Hi Polama,

I'm 99.99% sure that's a shogi board, and not a goban. (From the photo; and the same reasoning as yours. )

The Kanji characters are likely either the name of the manufacturing company,
or the family name of master craftsperson who made it (or both):

保尾 ( written and read top to bottom in your photo; and left to right in this post )

Someone else more proficient can help with the Japanese pronunciation of this name.
A quick search shows at least two pronunciations: やすお (yasuo) and ほお (hoo).

Based on the photos, I'm guessing the board could be 100 years old (or even older).
But I suppose poor maintenance could also turn a WWII-era board into that condition, which would mean younger.

( Random related factoid: Takao Shinji's family name is Takao 高尾 , sharing the same Kanji 尾 (o). )