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In the title compound, C13H9ClN4O4, there are two crystallographically independent molecules in the asymmetric unit, which have very similar conformations. The C=N—N angles in each independent molecule are 115.0 (2) and 116.6 (2)°, which are significantly smaller than the ideal value of 120° expected for sp2-hybridized N atoms. This is probably a consequence of repulsion between the nitrogen lone pairs and the adjacent N—N bonds. Two bifurcated intramolecular N—H...O hydrogen bonds help to establish the molecular conformation and consolidate the crystal packing.