That's a grey area. It may still be considered to be a work made for hire and so the employer would own the copyright. https://www.copyright.gov/circs/circ09.p

That's a grey area. It may still be considered to be a work made for hire and so the employer would own the copyright. https://www.copyright.gov/circs/circ09.pdf https://www.copyright.gov/circs/circ09.pdf