The songwriter share is the 50% of publishing royalties that goes directly to the songwriter (or co-writers) and cannot be claimed by a music publisher under standard publishing deals. The other 50% is the publisher share.

This split — songwriter share / publisher share — is the industry convention dating back to early 20th-century music publishing. A 75/25 publishing deal means the publisher takes 75% of the publisher share (37.5% of total), leaving the writer 100% of the songwriter share (50%) + 25% of the publisher share (12.5%) = 62.5% of total royalties.

A pure admin deal at 20% commission means the songwriter keeps 80% of total royalties (admin takes 20% of the gross, not split-side specific).

Understanding the split is essential when evaluating deal offers — what looks like a "75/25 deal" actually means 62.5/37.5 in net royalty share.