Method and valve for the venting of a saddle fuel tank

It is proposed a method for venting of a liquid tank (100), the tank comprising a valve (200), a primary compartment (102) and a secondary compartment (103) which are connected together in a communicating manner by means of a bridge (104). The valve is such that it comprises: a) a chamber provided with a cover, which extends at least partly into the tank and is connected via an upper venting aperture (203) to a venting circuit; b) first means (206) for monitoring a level of liquid in the primary compartment; c) second means (207) for monitoring a level of liquid in the secondary compartment; The valve is such that it is configured to be closed when: - said first means detect that the level of liquid in the primary compartment is equal to or higher than a first predetermined filling level (L1); and - said second means detect that the level of liquid in the secondary compartment is equal to or higher than a second predetermined filling level (L2).