Once the agency has covered their costs and taken out their desired profit margin, the rest is left for the nurse to potentially get. When a travel nurse is negotiating pay, they are usually negotiating to get 100% of what is left after the agency takes out the amount needed to cover all costs and meet the desired profit margin. 

However, at this point, some recruiters/agencies will try to take even more of what is left over because they want to make as much profit as possible. 

The amount the nurse is able to negotiate is broken down into a pay package. 

Hospital > Bill Rate > Agency > Pay Package > Nurse