Energy sector-related exchange traded funds gained Tuesday after Warn Buffett’s Berkshire Hathaway’s latest regulatory filing revealed increased purchases of Occidental Petroleum Corp. (OXY) to near a threshold that would include the oil company’s earnings for its own. On Tuesday, the Invesco Dynamic Energy Exploration & Production Portfolio (NYSEArca: PXE) gained 4.0%, the First Trust Energy [...] The post Energy ETFs Gain as Buffett’s Berkshire Hathaway Ups Occidental Stake Again appeared first on ETF Trends .