The title mol-ecule, C(14)H(14)O(3), contains two fused six-membered carbon rings with keto groups at positions 1, 4 and 5 and a gem-diethyl group at position 8. The mol-ecule is close to planar (maximum deviation = 0.044 Å), with one ethyl group at each side of the mol-ecular plane, with exception of the keto group at position 1 which is slightly deviated from the plane and disordered over two positions one on each side of it (occupancies 0.80/0.20). The packing of the mol-ecule shows weak bonded chains along a through C-H⋯O contacts and two intramolecular C-H⋯O interactions are also present.