After having class certification denied and losing a partial summary judgment motion, plaintiff entered into a stipulation with defendant for a voluntary dismissal so he could appeal. However, the stipulation reserved his right to appeal only the summary judgment and class certification rulings, not an earlier dismissal of a claim on a motion to dismiss. This decision holds that by not reserving the right to appeal from that order, plaintiff waived any error in dismissal of that claim and could not raise that issue on his appeal.