X0306 4 2015-02-11 1 0000351231 DAWSON OPERATING CO DWSN 0001410418 Thomas James W 508 W. WALL, SUITE 800 MIDLAND TX 79701 0 1 0 0 EVP, Chief Technical Officer Common Stock $0.33 1/3 par value 2015-02-11 4 D 0 22991 D 0 D Stock Options (right to buy) 18.91 2015-02-11 4 D 0 5000 D 2018-12-02 Common Stock 5000 0 D Disposed of pursuant to the merger (the "Merger") of Dawson Operating Company, previously known as Dawson Geophysical Company ("Old Dawson") with a subsidiary of Dawson Geophysical Company, previously known as TGC Industries, Inc. ("New Dawson") whereby each share of Old Dawson common stock, par value $0.33 1/3 per share, was converted into 1.760 shares of New Dawson common stock, par value $0.01 per share, having a market value based on the closing price of one share of New Dawson common stock on NASDAQ on the effective date of the Merger of $5.85 (as adjusted to reflect New Dawson's 1-for-3 reverse stock split, which occurred immediately prior to the Merger) per share and a cash payment being made for any fractional shares. Includes 7,932 Restricted Stock Units, which are convertible at a rate of 1 unit for 1 share of Old Dawson common stock, par value $0.33 1/3 per share. Each such unit was disposed of pursuant to the Merger in exchange for 1.760 corresponding units of New Dawson, subject to the same terms and conditions. Includes 9,000 Restricted Stock Grants, which are convertible at a rate of 1 restricted share for 1 share of Old Dawson common stock, par value $0.33 1/3 per share. Each such restricted share was disposed of pursuant to the Merger in exchange for 1.760 corresponding restricted shares of New Dawson, subject to the same terms and conditions. This option, which was vested, was assumed by New Dawson pursuant to the Merger and replaced with an option to purchase 8,800 shares of New Dawson common stock for $10.75 per share. /s/ James W. Thomas 2015-02-12