Bucket opening tool

One of my first design jobs fresh out of school 30 years ago was to design a bucket tool, one that sliced the slots in the lid, pried the lid off and then could be used to hammer the lid back on and; Oh! it has to beat this patent that centered around the sentence "having a pivot on an arm depending from the main lever". 
I thought if we put some changes in direction in the main arm to form the pivot and other functions, that might do. The result was a unique Klingon warrior-looking tool I was pretty happy with.
Well, I was recently at my local sculpture supply store and found a cheap copy, albeit smaller with some cost saving details. Even the process- sandcasting- was the same, using the same standard casting-industry lettering that our client thought adequate. I'm flattered! The biggest operational difference is that we thought the actions should be the same, pivot the handle down to both cut and pry. Theirs, you lever down to cut, then lift up to open. 

How to use the tool. Nice to see it's still in production 30 years later.