A former hair stylist for Nicki Minaj is suing the star for $30m (£18m), accusing her of selling wigs based on his designs without permission.
Terrence Davidson began working for the rapper in 2010, creating multiple wigs for high-profile events and her Super Bass music video.
Mr Davidson claims he had previously discussed a joint business venture with Minaj to launch a line of wigs.
Representatives for Minaj have yet to comment on the legal action.
Mr Davidson says the star is now copying his wig designs and selling them online.