X0202 4 2007-04-03 0 0000026537 ARGON ST, Inc. STST 0001305061 Sellier Victor F 12701 FAIR LAKES CIRCLE FAIRFAX VA 22033 1 1 1 0 Vice President Common Stock 2007-04-03 4 S 0 40000 D 1596117 D Common Stock 928803 I Trust Average price $27.6420 per share The sale was made pursuant to a 10b5-1 trading plan entered into by Mr. Sellier on December 29, 2006. Shares were disposed of in multiple transactions on April 3, 2007 as follows: 6200 shares @ $27.5000 400 shares @ $27.5100 200 shares @ $27.5200 1106 shares @ $27.5300 394 shares @ $27.5400 400 shares @ $27.5500 100 shares @ $27.5600 300 shares @ $27.5700 1890 shares @ $27.6100 3610 shares @ $27.6245 500 shares @ $27.6300 1800 shares @ $27.6445 2300 shares @ $27.6500 1900 shares @ $27.6600 3700 shares @ $27.6700 1900 shares @ $27.6800 2300 shares @ $27.6900 3900 shares @ $27.7000 600 shares @ $27.7100 250 shares @ $27.7200 1300 shares @ $27.7330 300 shares @ $27.7400 2950 shares @ $27.7500 500 shares @ $27.7600 400 shares @ $27.7700 600 shares @ $27.7800 200 shares @ $27.7900 /s/ Victor F. Sellier 2007-04-05