Conventional Common Law reasons for finding a Contract VOID ab initio.

• Fraud in the Factum, ie: Fraud as to the Nature of the contract.
• Absence of mutual assent
  • Mutual Mistake about the essential nature of K
  • Ambiguity or Misunderstanding
    • If Neither or Both were aware of ambiguity
      • Different intent -> VOID
      • Same intent -> ENFORCEABLE
    • If One party was aware of ambiguity
      • Other parties belief prevails -> ENFORCEABLE
    • If Offeree doesn't understand offer:
      • Negligent failure to read or understand -> ENFORCEABLE
      • Fraudulent misrepresentation by Offeror:
        • Contract formed based on Offeree's understanding
        • blanket recitals of understanding may be ineffective
  • Absence of Consideration: A party had no real obligation.
  • Illegality, unless parties not 'in pari delicto'