Last spring, Niki Christoff, a senior Salesforce executive, was offered an opportunity to join the board of a publicly traded company alongside her day job. Being a director of a public company is a corporate badge of honor, and the invitation signaled she was poised to break into a club long dominated by men.Ms. Christoff, Salesforce’s senior vice president for strategy and government relations — and one of the “25 Most Powerful Women in Politics,” according to Fortune magazine — was inclined to accept the invitation. So she sought permission from Salesforce.That’s when things got complicated.“I was told …
