I see another issue. it's a question of whether member B has $5,000 of basis to take his share of the loss. if one argues that A gifted 50% of the $10K (as a capital contribution) to B. then B has no obligation to repay A. if he does, then one can argue no gift was made and B has no real basis. this is a situation that should be discussed with a tax pro. Certainly, others can have different viewpoints.
