Where does the handoff line sit when a client asks for the raw footage and the prompt library

Picture a two year retainer, video and social for a small brokerage, ending on good terms. Then the request comes in: all raw footage, the edit project files, the content calendar template, and the prompt library built for that brand voice. The footage is usually the easy part to hand over. The client paid for the shoots, and it covers their properties and their people. The prompt library is where it gets harder. Say it represents forty hours of iteration, tuned to one client's voice but built on a base structure an operator reuses across several accounts. Hand it over and a competitor's future vendor inherits the method. Most contracts say work product delivered under the agreement belongs to the client, often written years before anyone thought to define whether a prompt is work product or a tool. There is a real argument that the client paid for those forty hours inside the retainer, so it belongs to them. There is an equally real argument that they bought outputs and the machinery isn't included, the way a photographer doesn't hand over lighting diagrams. Neither reading is clean, and it isn't worth litigating over an account that ended well. Where the line sits ultimately needs a specific lawyer conversation, since how a work product clause reads varies by state and by the actual wording. Worth discussing first is where operators think the line should sit before it ever hits the contract.