In music who decides how much writing credits you get?

The lead writer decides how the credit percentages are distributed. The song he helped write for Britney was called "Me Against The Music".

Here is a little history about what happened during that time:

When The Dream worked on Britneys song, he was still new to the industry.

Tricky Stewart was the lead writer and asked him to become part of the team. There ended up being a total of 7 co-writers for that one song he wrote for Britney.

Tricky and Penelope Magnet(one of the other writers) wrote the majority of the song, before The Dream was even hired, AND they are the only ones who got production credits on the track..Those two definitely got the bigger credit percentages.

After the song was finished, Britney invited Madonna to feature and write a verse for herself on the track, because they became friends and were getting so much attention for their 2003 VMA kiss.

This meant that Tricky and Penelope Magnet had to readjust the percentages and also rework the song''s production to include Madonna's part.

The Dream did not get a single 'production credit' on the song. He only got a co-writing credit with six other people. Britney hired Tricky and Tricky hired The Dream. If he felt cheated, it was done by Tricky.

Honestly, the track was not that great and its definitely Britney's worst lead single. The best thing about that song was the dance choreography created by Columbus Short. I do like the song though.