X0303 4 2010-05-18 0001409375 ORION ENERGY SYSTEMS, INC. OESX 0001418607 Scribante John H 2210 WOODLAND DRIVE MANITOWOC WI 54220 1 President-Orion Tech. Ventures Common Stock 23815 I By Garden Villa on 3d LLC Stock Options (right to buy) 3.46 2010-05-18 4 A 0 16731 0 A 2020-05-18 Common Stock 16731 16731 D Stock Options (right to buy) 2.25 2014-07-31 Common Stock 25000 25000 D Stock Options (right to buy) 2.5 2016-06-02 Common Stock 40000 40000 D Stock Options (right to buy) 5.35 2018-08-08 Common Stock 21452 21452 D Stock Options (right to buy) 3.78 2019-05-19 Common Stock 11759 11759 D Stock Options (right to buy) 3.01 2019-09-01 Common Stock 250000 250000 D Grant to reporting person of option to buy shares under the 2004 Stock and Incentive Awards Plan. This option, granted May 18, 2010, vests and becomes exercisable in 20% increments on May 18, 2011, 2012, 2013, 2014 and 2015, respectively. Grant to reporting person of option to buy shares under the 2003 Stock Option Plan. This option, granted July 31, 2004, vests and becomes exercisable as follows: 10% on August 1, 2004, 30% on March 31, 2006, 50% on March 31, 2007, 70% on March 31, 2008, 90% on March 31, 2009, and 100% on March 31, 2010. Grant to reporting person of option to buy shares under the 2004 Equity Incentive Plan. This option, granted June 2, 2006, vests and becomes exercisable in 20% increments on March 31, 2007, 2008, 2009, 2010 and 2011, respectively. Grant to reporting person of option to buy shares under the 2004 Stock and Incentive Awards Plan. This option, granted August 8, 2008, vests and becomes exercisable in 20% increments on August 8, 2009, 2010, 2011, 2012 and 2013, respectively. Grant to reporting person of option to buy shares under the 2004 Stock and Incentive Awards Plan. This option, granted May 19, 2009, vests and becomes exercisable in 20% increments on May 19, 2010, 2011, 2012, 2013 and 2014, respectively. Grant to reporting person of option to buy shares under the 2004 Stock and Incentive Awards Plan. This option, granted September 1, 2009, will vest and become exercisable in 50,000 share increments when the average trading price of the Issuer's common stock equals or exceeds $4.00, $5.00, $6.00, $7.00 and $ 8.00 per share. /s/ Peter C. Underwood, Attorney-in-Fact 2010-05-20