Given recent market trends and the rising significance of the healthcare industry, Warren Buffett has been betting on AbbVie (ABBV) and Merck (MRK), as revealed in Berkshire Hathaway’s latest 13F filing. However, we think the macroeconomic and exogenous headwinds faced by Chevron (CVX) and Charter Communications (CHTR)—which are also held by Berkshire—make them best avoided now. Read on.