Hello and welcome to Just Answer. I have 20 plus years experience in all areas of US taxation including multi-state and international issues.
The IRS will look to the "cause of action" for determining how the settlement payments are taxed. Therefore, the wording in the original lawsuit and the settlement agreements will be key in determining how the settlement payments are taxed. Even though it would be preferable to have the allocation actually made in the settlement agreement, it may still be possible for you to make a reasonable allocation, depending upon the wording in the lawsuit and the settlement agreements. I do suggest that you be sure a proper allocation is made in any future settlement agreements.
I hope this helps. Let me know if need further assistance. If you could provide more of the facts surrounding the "cause of action" I may be able to give you some direction.