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Modifications and the Pre-existing Duty Rule: Discussions in Contracts Podcast

The topic of this podcast is when contract modifications are not enforceable due to the pre-existing duty rule. Consideration is required to support enforcement of an agreement, including a modification to an agreement. In this podcast, we will look at when the pre-existing duty rule renders modifications unenforceable and when the modern common law rule and the rule of UCC § 2-209 permit enforcement of some modified agreements in the absence of new consideration. 


Learning Outcomes


On completion of the lesson, the student will be able to:


  1. Explain that a modification of a contract has to be agreed to by the parties.
  2. Explain that modifications follow the same rules of assent as apply to the formation of contracts. 
  3. Identify and apply the pre-existing duty rule that requires modifications to be supported by new consideration to be binding.
  4. Explain and apply the modern common law rule that permits modification without new consideration if there are unforeseen circumstances, and the modification is fair and equitable. 
  5. Explain and apply the rule of UCC § 2-209, which also validates contracts as modified without new consideration.

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