On April 1, 1944, del Valle, as Commanding General of the Third Corps Artillery, III Marine Amphibious Corps, took part in the Battle of Guam and was awarded a Gold Star in lieu of a second Legion of Merit. The men under his command did such a good job with their heavy artillery that no one man could be singled out for commendation. Instead each man was given a letter of commendation by del Valle, which was carried in his record books.