Two questions about this Deba

[joostvdwerf]

I just bought this pre-owned Deba from Japan. All information the seller gave me, it has a white steel core and made in Sakai. Makes me wonder:

1. Do any of you read kanji? Can you help me get more info on the maker?

2. Who knows what the damage on the spine could have come from? My thinking is the previous owner used another knife to hit the spine when chopping off fish heads..?

Thanks a lot for your help!

 

[Greasylake]

Looks like a mix of kana with a kanji at the end. Maybe, すみミザ川? Googling that didn't take me anywhere, so the last two kana might be something different. Marks on the spine are probably from a hammer, they are pretty common on used debas in Japan