"Fabricate" is related to this verb that can mean to write something fraudulent, like a signature
[DOC] [TLE] Forge - definition of forge by The Free Dictionary [PAR] To give form or shape to, especially by means of careful effort: forge a treaty; ... (
Metallurgy) to make or produce a fraudulent imitation of (a signature, ... [1250
1300; Middle English < Old French forgier < Latin fabricre to fashion; see 
fabricate] ..... verb.