Which factor is NOT necessary for independent federal jurisdiction over state law claims?

Independent federal jurisdiction over state law claims is primarily governed by two key factors: either the existence of a federal question or diversity of citizenship. When a federal question is present, the federal courts have original jurisdiction over the case. Similarly, in cases of diversity jurisdiction, the parties must be from different states, and there must also be an amount in controversy that exceeds $75,000.

The reason that the relation to a common contract agreement is not necessary for independent federal jurisdiction is that it does not establish a basis for federal jurisdiction on its own. While contracts can be involved in cases that invoke federal jurisdiction, their mere existence or relation is not a requirement for a federal court to have jurisdiction over state law claims. In contrast, the other options directly reflect the fundamental criteria needed for a federal court to hear a case.

This distinction is crucial in understanding how federal jurisdiction operates, particularly when assessing whether a particular claim or case can be brought in federal court in the first place.