I thought that this was spelled “gewusst”…and the “u” is short…is this an older spelling, pre-spelling reform?
1 Like
To me it seems correct, it is what I learned in school, but the form with the “ss” would technically not be incorrect either.
According to Wikipedia apparently they did stop using the ß in Swiss Standard German
ß - Wikipedia last century, but in Standard German it is still used.
English Translation
I didn’t know anything.
It’s not correct after the 1997 reform anymore
1 Like
Yes. It predates 1996. I’ve never in my life seen that spelling until now. “gewußt” is officially wrong since almost 30 years. 
And you’re absolutely right. 
I reported the misspelling to have it corrected.