CoB NO excess capacity
TP = VC + Opp Cost
CoB has excess capacity
TP = VC
CoC NO outside supplier
TP = SP - VC
CoC has Outside supplier
TP = SP of supplier
CoB bears TC
TP + TC
CoC bears TC
TP - TC
Forced internal transfer
Cost of internal transfer = x
Cost of external transfer = y
Benefit/loss to CoA from internal transfer = y - x
if y-x > 0, Benefit
y-x < 0, Loss
Why Force internal transfer
Prevent signaling of poor quality or service due to sister companies not buying their own products.