Summary: Stocks were off their highs in midday trading Friday after a strong start but are still at record levels. Dow Industrials are gaining in the triple digits. Energy and material sectors are leading the markets. Shares of Nabors (NBR) and Halliburton (HAL) are both up better than 3%. Caterpillar (CAT) is the blue chip's best performer, rising more than 4%. Changes at the top are leading Sotheby's (BID) and Hertz (HTZ) to the upside. Sotheby's is soaring after its CEO said he will step down from the auction house. Hertz investors are also welcoming a new CEO, who is replacing a resignation in September. Foot Locker (FL) is losing its footing and dropping despite posting better-than-expected earnings before the bell.
