As noted below, much of that information was provided by the UN and it is the UN which must waive confidentiality.
The Prosecutor has said of his appeal:
I am ambivalent about this. If "the basic framework to solve this particular problem is settled" means that the UN will now allow the defence and the Court to see this material in a full and proper way, then that's fine.
“The Foundations of the ICC have to be based on high standards and efficiency ... We will harmonise fair trials with respect for the institutions that provide information to us. The basic framework to solve this particular problem is settled with the UN and we will explain this clearly to the judges”.
If, however, the words "the basic framework ... is settled" and the worrying references to "efficiency" and "respect for the institutions that provide information" all add up to an assertion that existing practices are fine and all that judges require is a clearer explanation on appeal, then we have a real problem.
The right to a fair trial cannot and should not be balanced against "efficiency" of the value of the ICC's working relationship with the UN. If the ICC cannot proceed with a trial fairly (a different thing from "perfectly"), it should simply not proceed at all.
Whatever the outcome of the Lubanga appeal, it looks set to have consequences for the new ICC cases opening against Congolese militia leaders Germain Katanga and Mathieu Ngudjolo Chui.