Last week marked the sixth anniversary of the July 12, 2016 international arbitral tribunal ruling on the South China Sea, a landmark case brought by the Philippines against China over the validity of Beijing's sweeping claims to the disputed waters.

Among other things, the tribunal ruled that China's argument of historic rights - used to buttress its claim to large parts of the strategic waterway and its resources - was invalid under international law. The verdict was a resounding legal victory for the Philippines, but one that China, which questioned the jurisdiction of the tribunal, rejected as null and void.