The latest trading session saw Phillips 66 (PSX) ending at $126.47, denoting a +0.78% adjustment from its last day's close. The stock trailed the S&P 500, which registered a daily gain of 1.77%.

Phillips 66's 356,500-bpd Wood River refinery is undergoing a turnaround, research company IIR Energy said. The refinery, in Roxana, Illinois, began maintenance activities last week, IIR said.