Problem
What is the holding of Marbury vs Madison? The holding (aka the Ruling or Principle of Law) states the rule of law as promulgated by the Court. Such rule becomes applicable thenceforth to all similar cases to be decided by state or federal courts (as long as the issue is constitutional and not a matter of, say, federal statutory interpretation). It, thus, sets a precedent by which similar cases in the future are to be decided (the doctrine of stare decisis). The holding should be stated in brief, clear, and precise language. In some cases, you may find it in the decision itself, usually toward the end of the decision.