U S. Patent No. 6,054,932 was issued and assigned to Traffic Technology Inc. on April 24, 2000. This is the second patent assigned to Traffic Technology Inc. It covers the addition of the white border to the red octagon for the Stop sign and uses an inverted triagle for Caution among the symbols in the Unilight.
This patent is also covered in foreign filings in 36 countries..

U.S. Patent No. 5,898,381 was issued and assigned to Traffic Technology, Inc. on June 17, 1997. This Method of Manufacture and Use patent covers the integration of three or more traffic signal faces displayed by LEDs through a single opening in a traffic signal housing.