By Sheila Dang and Shadia Nasralla Exxon and Shell maintain buybacks amid oil price slump Chevron and BP reduce buybacks due to market conditions Exxon benefits from Guyana oilfield, Chevron seeks entry HOUSTON/LONDON, May 2 (Reuters) – Big Oil’s first-quarter earnings have shown a clear split in how companies are positioned to weather the downturn … Read more