The resm-i hınzır ("Pig tax") was a tax on pigs in the Ottoman empire.
[1] Although pork was theoretically banned in the Ottoman empire, some trade continued - alongside trade in alcohol.
One fatwa specifically claimed the resm-i hınzır (along with the resm-i arusane, a bride tax) should end; but the trade, and the tax on it, continued regardless - occasionally disguised as "gifts".
[2]