Art. XXIX. An individual cannot be considered a spy unless, acting clandestinely, or under false pretences, he obtains, or seeks to obtain, information in the zone of a belligerent's operations, with intent to communicate it to the opposite party. Military persons, therefore, who, not being in disguise, have penetrated into the zone of operations of the enemy's army, with a view to obtain information, are not to be considered as spies In the same manner military persons or civilians charged with the conveyance of despatches to their own army or to that of the enemy, and executing their mission openly, are not to be considered as spies. To this class belong, also, persons who are sent in balloons to transmit despatches, and, in general, to keep up communications between separated parts of an army or territory.

Art. XXX. A spy taken in the act cannot be punished without a preliminary trial.

Art. XXXI. A spy who, having rejoined the army to which he is attached, if subsequently captured by the enemy, shall be treated as a prisoner of war, and shall incur no liability for his previous acts of espionage.