forger

[Cf. F. forgeur metal worker, L. fabricator artificer. See Forge, n. & v. t., and cf. Fabricator.]
One who forges, makes, of forms; a fabricator; a falsifier.

2. Especially: One guilty of forgery; one who makes or issues a counterfeit document.

noun

One who makes a fraudulent copy of something: counterfeiter, fabricator, faker. See true/false.

The noun has 2 meanings:

Meaning #1: someone who operates a forge

Meaning #2: someone who makes copies illegally
  Synonym: counterfeiter