All returns are divided between the two parties based on their actual investment duration. Meaning that the seller is entitled to all interest payments made before they sell their claim, while the buyer receives all interest payments after they purchase the claim. However, the seller can choose to sell at a more expensive rate (up to the amount of unreceived interest), although such a sale is unlikely to attract a buyer.
If the buyer purchases a loan that is in debt, meaning that certain penalties, indemnities or interest payments have not been done and the claim exists, then all claims will belong to the buyer. Once the seller has sold an investment, they have no future claims to any of the proceedings.