On this section of motorway, the black vehicle does not intend to overtake. Can it travel in the left lane?

When travelling on interurban roads, the right-hand lane must always be used. If travelling on one-way carriageways with more than one lane in the same direction, the other lanes may be used when intending to overtake and to remain in the lane used in order to continue overtaking other vehicles, provided that vehicles travelling behind are not inconvenienced. Once the overtaking manoeuvre is completed, the driver must return to the right-hand lane.
If the vehicle in the photograph does not intend to overtake, it must return to the right-hand lane and travel in it.