However, the arbitrator noted that Spain could not legally grant what it did not hold and that the Treaty of Paris could not grant Palmas to the United States if Spain had no actual title to it. The arbitrator concluded that Spain held an inchoate title when Spain "discovered" Palmas. However, for a sovereign to maintain its initial title via discovery, the arbitrator said that the discoverer had to actually exercise authority, even if it was a simple act such as planting a flag on the beach. In this case, Spain did not exercise authority over the island after making an initial claim after discovery, so the United States' claim was based on relatively weak grounds.