Oracle combination of the context-only systems using GloVe and BERT. min and max denote the minimum and maximum F1 of the systems combined and comb denotes the F1 of the combined system. The first two panels were trained on the Original English CoNLL 03 training data and tested on the original English CoNLL 03 test data and the WikiGold data. The last panel was trained and tested on the respective splits of MUC-6.