Definition
An agreement between an employer and employee in which the employee agrees not to join or remain a member of a labor or employer organization. Yellow dog contracts are generally illegal.
Illustrative caselaw
See, e.g. Lincoln Federal Labor Union No. 19129 v. Northwestern Iron & Metal Co., 335 U.S. 525 (1949).
See also
29 U.S.C. § 103(a)-(b): nonenforceability of yellow dog contracts