A more thorough explanation:

The corporate-opportunity doctrine is a rule that prevents a corporation's directors, officers, and employees from using information they gained while working for the corporation to take personal advantage of any business opportunities that the corporation has an expectancy right or property interest in, or that should belong to the corporation in fairness.

For example, if a corporation is considering investing in a new technology, and an employee learns about a similar technology that could be profitable, the employee cannot use that information to start their own business or invest in the technology themselves. This would be a violation of the corporate-opportunity doctrine.

In a partnership, the analogous principle is called the firm-opportunity doctrine. This means that partners cannot take advantage of business opportunities that belong to the partnership for their own personal gain.

Overall, the corporate-opportunity doctrine is in place to ensure that corporations and partnerships are protected from individuals who may use their position to benefit themselves at the expense of the organization.