X0101 EFFECT 33 LIVE 2017-10-02 17:00:00

S-3

0001405073 Approach Resources Inc 333-220489 0001481181 Approach Resources I, LP 333-220489-06 0001481182 Approach Oil & Gas Inc. 333-220489-05 0001481184 Approach Operating, LLC 333-220489-04 0001481185 Approach Delaware, LLC 333-220489-03 0001481186 Approach Services, LLC 333-220489-02 0001576687 Approach Midstream Holdings LLC 333-220489-01