I am not a music lawyer so please don’t take the following as legal advice, I do however deal with issues like this for projects I work on.

Furthermore, I can’t really speak on mixing music for individual music clients, but I have extensive experience producing, composing, and mixing audio for commercial use, and the following concepts may apply to you – not necessarily in this case, but certainly for future projects.

Short Answer:

Q: “I mixed a song … who technically owns those tracks?”

It depends on your initial agreement with the client, but if it is not your music, i.e., you did not produce it, compose it, or arrange it, it isn’t yours. Most recording and mix work is done on this basis.

You do the job, get paid, deliver the goods and move on.

Also, to be honest, if a client is asking for individual tracks of an already mixed track you probably don’t want credit for what they are going to do with them anyway…

Furthermore, if you have done a good job mixing, the processed, individual tracks probably sound like ass on their own, so maybe explaining that to the client (using less vulgar terminology) will sway their request.

Longer Answer:

Q: “What is the norm in the industry?”

For freelance commercial audio – pre-post and post-production – almost all work is done on a work-made-for-hire basis, especially when dealing with “big” clients.

What that means is you do the work, they pay for it, and they own it outright. They can do what they like with it. No residuals, no royalties, no credits (unless otherwise stipulated, and even then not usually given). This is often offset by an inflated flat fee to compensate for future “lost” revenue.

Q: “Who technically owns those tracks?”

The person paying for the work, not you, is treated as its author.

Work Made for Hire: What It Really Means

Essentially, if the client paid you to mix something, and that is your only contribution to the project, it is their prerogative to do what they wish with any finalised material you hand over, even have it mixed by someone else – it’s their property.

Unless you have negotiated a clear and legal stake in the work, or added significant artistic content (like re-writing lyrics or musical parts, amongst others), any issue with client requests is like being a mechanic getting angry at a customer for wanting their car back after a tune up.

Q: “Is there any reason to or not to give him the tracks?”

Mr De Gonzaga Sevilla brings up a good point about being very clear on what it is you are being paid to do – if the client paid for a mix that is what they get, if they want stems or multi tracks at the end of the session they must stipulate that, and you must agree (or not) before work commences.

It is also more workload, so fees go up.

You’d be amazed how rapidly client requests abate once added fees are mentioned…

Finally, I cannot stress how important it is to get all work agreements in some form of writing – the humble e-mail. While not legally watertight, some form of “agreed in writing” is pure CYA (Cover Your Ass) for scope creep.

Scope creep (also called requirement creep, function creep and feature creep) in project management refers to uncontrolled changes or continuous growth in a project’s scope. This can occur when the scope of a project is not properly defined, documented, or controlled. It is generally considered harmful. – Scope creep – Wikipedia

So for example, now that your client is asking for multitracks you can go back through your e-mail chain with them and point out that in such and such an e-mail, dated xx xx xxxx, you made it clear that no multitracks would (or could) be delivered, only a stereo premaster at xx levels and mixed down stems of predetermined groups (like EFX, Voice Over, and Music, as a plastic example). Without that e-mail the client can claim you did agree, but just forgot, and it becomes a he said she said scenario.

Always ugly.

Actually, by using your own statement, “I don’t want CLIENT (“Him”) taking parts of my mix and using them without giving credit.” you have a basis for part of your “contract” with “Him”, and somewhere in e-mails with him you should have this explicitly mentioned. (Although, this wording means as long as he credits you, you’ll hand over the multitracks, so be careful. What do you really want to have? Control over your final mix, or that you are credited fairly?)

Personally, I do not hand over bits and pieces to the client, they get a polished stereo premaster, unless otherwise requested, and all of that is fleshed out in documentation and meetings long before work even starts. My resources, responsibilities and deliverables are very clearly outlined from the beginning, and such methodology largely mitigates issues like the one you are having.

Congrats on getting some paid work. I know the info here might not help you right now, but I hope some of it aids you in your future endeavours.