This section is from the book "The Law Of Contracts", by William Herbert Page. Also available from Amazon: Commercial Contracts: A Practical Guide to Deals, Contracts, Agreements and Promises.
In order to sustain an action for interference with contract, it has been said that it must appear that there is a valid and enforceable contract, which has not been discharged, for interference with which damages are sought.1 If A holds an option on B's property, which has expired, X's act in informing B that such option is not valid and in buying such property from B does not give to X a right of action against A.2 If the contract of employment between A and B is unenforceable because of the Statute of Frauds, and if B has notified A that he intends to repudiate such contract before X has attempted to entice B away, A has no right of action against X for enticing B.3 If A acquiesces in B's breach and treats the contract between A and B as ended, it is said that A has no right of action against X for inducing B to refuse to perform such contract.4 In these cases, however, it is not shown that B would have performed but for X's interference, or else it is shown that A acquiesced in B's breach and treated the contract as discharged.
A may, however, be willing to enter into an agreement with B, which does not amount to an enforceable contract, and he may be willing to rely upon B's honor or B's willingness to perform; and in such cases he may be even more seriously injured by X's interference than he would be if the contract were a valid and enforceable obligation, since in the latter case he would have a cause of action against B for breach of contract, whether he had one against A for interference with contract or not. For these reasons it is held in some jurisdictions that if the agreement between A and B would have been performed by B but for X's, interference, A has a cause of action against B, even though the agreement was not an enforceable contract.5 If B would have performed but for X's interference, the fact that A can not enforce such contract against B by reason of the Statute of Frauds, is not a defense to X, if B did not repudiate for that reason.6
11 Doucette V. Sallinger, 228 Mass. 444, 117 N. E. 897.
12Wissmath Packing Co. v. Mississippi River Power Co., 179 Ia. 1309, L. R. A. 1917F, 790, 162 N. W. 846.
1Kock v. Burgess (Ia.), 156 N. W. 174 [rehearing denied, Kock v. Burgess (Ia.), 158 N. W. 534]; Swain v. John-eon, 151 N. Car. 93, 28 L. R. A. (N.S.)
615, 66 S. E. 619; Poston v. Lyerly, 105 S. Car. 37, 89 S. E. 392.
2 Swain v. Johnson, 151 N. Car. 93, 28 L. R. A. (N.S.) 615, 65 S. E. 619.
3 Poston v. Lyerly, 105 S. Car. 37, 89 S. E. 392.
4 Kock v. Burgess (Ia.), 156 N. W 174 [rehearing denied, Kock v. Burgess (Ia.), 158 N. W. 534].