The act of taking something on fire, like a cigarette, and sharing this fire with others by placing the lit end on the outer unlit end of your friend's cigarette. This infringes on the person who gave you a license to burn your cigarette. The idea is that the fire is the intellectual property of whoever gave it to you, and you're only allowed one copy.
Pyropiracy is very harmful to the match and lighter industry by infringing their reserved rights.

Bill Gates:How did you light that cigarette without a lighter?
Warezman:Pyropyracy.
FBI:I charge you with pyropiracy. Pay me $250,000!
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