Having observed boat activity at the shoal that could have signaled preparation for development activity, the U.S. "flew three different air patrols near Scarborough ..., including on April 19 and 21", 2016, and talked of and reportedly were considering other reactions in light of generally higher tensions in the Spratlys and the region. The U.S. flights did observe the 12-mile territorial limit from the shoal.Lubold, Gordon, and
