Stocks to watch Friday: Aon, Merck, Amgen By: MarketWatch July 28, 2011 at 16:49 PM EDT Among the companies whose shares could see active trade in Friday’s session are Aon, Merck and Amgen. Read More >> Related Stocks: Amgen Chevron Corp McKesson Corp Merck & Co Newell Rubbermaid Starbucks Corp Weyerhaeuser Co