The clear purpose of the company’s moonlighting rule is “to prevent employees from taking outside employment that adversely affects their work for the Respondent,” and interpreted in light of that purpose, the board concluded that the reasonable employee would not draw the conclusion that the rule would “prohibit[] the protected activity of part-time work as a union salt that did not interfere with their ability to perform their duties for the Respondent.” Thus, this moonlighting rule and others similar to it pass muster under the Board’s Boeing scheme.