Ken in Texas said:
I recently shot some photos and video of a vacant lot for a Realtor. I asked him if he wanted music on the video and he declined. A few days later, I saw the video on his YouTube channel and he had added music to it. He also linked to that video from other real estate sites.
The contract I have with him has this wording in it regarding copyright: "All images and videos produced by Company remain the property of Company and are protected under USA and International copyright laws. Company may use the images and videos for the promotion of Company business.
Company grants to Client exclusive license to use the finished Product for purposes of promoting Client’s business or other uses. Client may not sell or transfer Product without prior written permission of Company."
Two questions: Has he violated my copyright? Should I have language in the contract that explicitly prohibits modifying the video to add music, titles, etc?
It doesn't sound like he's violating your copyright to me. If the client is using the video to sell the property you shot, there's no problem. Transfering the video means giving or selling it to some other party.
As for not allowing clients to modify your video, that's up to you to decide but I don't see any point asking him not to adding music or titles. This is beyond most Realtors technical ability but I don't see that it's a big problem.