Company Z sued the Company A and a former Company Z executive who has been tapped by Company A to run its China operations. Company A is a Delaware corporation with its headquarters in California. Company Z is also a Delaware corporation but with its headquarters in Oregon. The suit was filed in a Oregon court against Company A and James Dean, who until recently was the corporate vice president of Company Z's Interactive Services Division. Company A said earlier Tuesday that Dean was joining the company and would head up a new research effort in China for the Search division. Dean started working for Company Z, in a Oregon office, in the mid-1990's focusing on R&D for faster searches. Fresh out of graduate school, Dean and Company Z did not sign an employment contract when he began working there. In the early 2000's Dean was promoted to lead the search development team at Company Z. This promotion was accompanied by a large pay increase and a new employment contract. The employment contact included a non compete clause stating that Dean could not work for any direct competitor of Company Z's for thirteen months after he left the company. On signing the new employment contact Dean received a bonus of $200,000. In December 2017 top Company Z executives met with Dean to discuss the poor performance of his development team. The development team was months behind on a key section of code. In that meeting Dean claims that the Company Z executives agreed to waive his non-compete clause if his team delivered the code in the next two months. The team successfully delivered the project before the new deadline and Dean began to look for a new job. In May 2018 both James Dean and Company Z mutually agreed to part ways, by September 2018 Dean had accepted a job at Company A.

Please identify the rule of law or case law that applies and explain?