A case caught my attention recently:
In it, person A commits both breach of contract and also the tort of deceit in lying about an asset they fraudulently sold for about 6 figures. In the civil case, the ostensible claimant is B who eventually reaches a pre-trial settlement of some amount over £30k in "full and final settlement of all claims between A and B from the transaction".
However there is also a 2nd potential claimant C (and perhaps others as yet unknown) who suffered loss due to the transaction being fraudulent. A knew that C would also suffer loss, but no exposure to a claim by C was contemplated by A at the time they settled with B. C and B kniw each other but C has mental health issues which meant they were unable to discuss their own harm suffered with B or combine the claims, and mentally also couldn't deal with their own case at that time. C's claim isn't as large (probably £5-10k), is well evidenced, and is not ruled out by the agreement of A and B. But the immediate rebuttal if C claims will probably be that the cases should have been brought together and is not able to be brought because of failure to follow court rules or combine the cases.
I'm not sure how strong a barrier this would be in UK law, and I'm curious.
Can C bring a case, or is C pre-emptorily barred by the fact that any case should have been brought a the same time and settled with A? Or is there just a penalty in costs? Was C under a duty to combine or just desirable in law to do so? What other arguments would strengthen C's position if the question comes up of failing to combine cases?