What is the result of failing to join transactionally related claims?

Failing to join transactionally related claims can result in a successful defense against those claims because it may lead to the invocation of a legal doctrine known as "res judicata" or claim preclusion. This doctrine stipulates that a party cannot bring a lawsuit on claims that were or could have been brought in a prior action involving the same parties and the same transaction or occurrence. If claims are not joined when they are supposed to, the defending party might argue that the plaintiff has waived their right to pursue those claims in the future.

By not bringing all necessary claims together, the plaintiff risks having the opportunity to recover damages or seek remedies for those claims lost, as the court may determine that they should have been included in the initial litigation. This situation emphasizes the importance of identifying and consolidating all claims related to a single transaction in a single lawsuit to avoid potential defenses based on the failure to join those claims.

In contrast, other options may imply incorrect or misleading consequences about the failure to join claims, such as indicating that they can be filed later without any repercussions, or suggesting automatic dismissal of the claims, which is not a direct result of failure to join. Therefore, the most accurate outcome is that such a failure could be leveraged as a defense