In copyright law, ownership of a copyright in a work originally vests in the author, the person who creates the work. The presumption is that the author owns the work. This presumption is excepted in some situations. For instance, when a work is specially commissioned, the hiring party is often considered the owner. Or if a work made for hire agreement has been written, the contract will specify who owns the copyright – the author or someone else. Or, if the work was created by an employee within the scope of employment.
It is usually pretty clear whether a person is an employee. There is often tax, payroll, control, and business evidence to demonstrate whether someone is an employee or not. Where an employment relationship exists, the work must be created within the scope of employment for the employer to be considered to copyright owner. Courts frequently define the scope of employment very broadly. Even if someone creates something on a home computer, outside of work hours, it might still be considered to be employer-owned if it is closely related to the work of the employer, or the work the employee typically does. Additionally, employee handbooks or policy manuals may define the scope of employment, normal job duties, or other aspects of work that may help color the analysis.
In short, determining whether an author is the copyright owner or a hiring party is the owner is vitally important in determining ownership of intellectual property rights, and subsequent licensing rights. There are no bright line rules on ownership, and a lot of factors can be considered when deciding who the copyright owner is. It is important to consult a competent intellectual property or employment attorney when tackling ownership issues like this.