Co-writing sessions and splits: how to run the room and agree shares before anyone leaves

A co-writing session is one of the best days in music and one of the easiest to get wrong. Three people spend six hours on a chorus, everyone leaves buzzing, and nobody writes down who did what. Eighteen months later the song gets synced, and suddenly everyone remembers the day differently.

This guide is about the day itself. Our guide to ISRC, ISWC and split sheets covers the paperwork and codes, and collecting royalty splits covers getting each share paid. Here we cover what comes before both: running the room so that the split you sign is one everybody actually agrees with.

This is general information, not legal advice. If real money or a publishing deal is involved, show the paperwork to a music lawyer.

Why the law makes this urgent

Most countries treat a song written together as a joint work, and the default rules kick in whether or not you sign anything.

In the US, a "joint work" is one "prepared by two or more authors with the intention that their contributions be merged into inseparable or interdependent parts of a unitary whole" (17 U.S.C. § 101). The authors of a joint work are co-owners of the copyright (17 U.S.C. § 201). The statute says they co-own it. It does not say in what shares. That gap is exactly what a split sheet fills.

The UK frames it differently. A work of joint authorship is one "produced by the collaboration of two or more authors in which the contribution of each author is not distinct from that of the other author or authors" (Copyright, Designs and Patents Act 1988, s.10). India's Copyright Act, 1957 uses almost the same wording in its definition of a "work of joint authorship" (section 2(z)).

Two practical points follow. First, intention and collaboration matter, so being clear in the room that you are writing together is part of the record. Second, if anyone later wants to give up or move their share, US law says a transfer of copyright ownership is not valid unless it is in writing and signed by the owner (17 U.S.C. § 204). A nod over coffee doesn't count.

Before the session: settle the ground rules

Do this by message the day before, so it isn't awkward in the room.

1. Agree the default. The simplest rule, and a common one in songwriting rooms, is an equal split between everyone who is in the room writing. Say whether that's your starting point. If someone expects a different arrangement (for example, they're bringing a finished verse and chorus), it must come up now, not after the song is good.
2. Say who is a writer. Producers, engineers and players may or may not be writing. Decide whether the producer is a co-writer on this song, or is being paid for production through points on the master. Our guide to producer agreements, points and splits explains the difference.
3. Collect details in advance. Legal name, writer name, collecting society (PRO) and IPI number, and publisher if any. Chasing these after the session is where weeks get lost.
4. Agree what happens to unused ideas. If a writer brings a hook that gets dropped, does it stay theirs? Usually yes. Say so.
5. Name the note-taker. One person owns the session record and the split sheet. Rotate it between sessions.

During the session: keep a running record

You don't need to log every syllable, but a short running record turns a memory argument into a document.

• Title and date at the top, plus a working title, because songs get renamed.
• Who arrived with what. "A brought the chorus melody from a voice memo dated 3 Oct." Keep the voice memo.
• Version saves. Save the DAW project with the date in the name at each milestone. A bounced rough at the end of the day, with the date, is a simple record of what existed when.
• Samples and interpolations. If anyone uses a sample or quotes another song, write it down now. That share isn't yours to split until it's cleared; see sample clearance basics.
• AI tools. If a generator or AI lyric tool was used, note which and for what. A clean note of who wrote what protects every human writer.

End of the day: agree the split before anyone leaves

This is the step people skip because everyone is tired and happy. Do it anyway. It takes ten minutes.

1. Play the rough back once. Everyone hears the same thing they are signing for.
2. State the proposed split out loud. Start from the default you agreed. Ask, plainly, "Is everyone good with this?"
3. If someone isn't, talk about the song, not the person. "The hook is what makes this work, and that was mostly B" is a better conversation than "I did more." Agree a number, even if it's provisional.
4. Write the song split, separate from anything else. The split sheet is for the composition: music and lyrics. Master ownership, producer points and session fees are different deals and belong on different paper.
5. Check the total is 100%. It sounds obvious, but it's an easy one to get wrong.
6. Sign. Everyone signs and dates it, on paper or with an e-signature tool. A photo of a signed sheet in the group chat is better than nothing; a PDF everyone has a copy of is better still.
7. Send it the same day. The note-taker sends the signed sheet and the dated rough to every writer before bed.

If you really can't agree on the day, sign a sheet that says the split is still open and lists what's disputed. That's still a written record that everyone co-wrote, and it should say that nobody releases or registers the song until the open item is settled.

After the session

The split sheet is the source every later registration copies. Each writer then registers the song with their own society using the same percentages, and the master and mechanical side are set up separately, as our royalty splits guide walks through step by step. If you write with the same people often, a short band agreement can set your defaults once so each session starts from a known rule.

What we think

The industry treats splits as admin. We think they're part of the creative culture of a room, and the best rooms say the number before they write a note. Agreeing an equal split in advance isn't about being generous. It removes the incentive to fight for credit while writing, so people take risks, throw out their own ideas and serve the song. A writer who is counting their lines is writing defensively.

There's a harder point for artists. The artist is usually the person with most leverage in a co-write, and that's exactly why they should be the one to raise the split first and offer the fair version. Writers remember who was straight with them. Over a career, the reputation for running a clean room is worth more than a few extra percent on any one song, because it decides who wants to write with you next.

And we'd push one habit above all: sign before you leave. Not "send it over later." Most of the split arguments we hear about sit in the gap between a great day and a piece of paper nobody got round to.