Appealing a UC Berkeley admissions decision involves submitting a formal request to the admissions office asking them to reconsider their initial decision. This can be done if you believe there was an error in the evaluation of your application or if you have new information to submit that you believe would strengthen your case for admission.
There are a few important things to keep in mind when filing an appeal. First, you should make sure that you have a valid reason for appealing. The admissions office will not reconsider your application if you are simply unhappy with the decision. Second, you should submit your appeal as soon as possible after receiving the initial decision, as there is a deadline for submitting appeals.