The sharp drop in Halliburton's share price was very likely due to a belief among investors that the company overpaid, the deal will never pass regulatory scrutiny — or even if the deal makes it past regulators Halliburton will have to divest some assets — or if Halliburton has to pay the $3.5 billion break-up fee that will be a downer for the stock. These same reasons are also dampening enthusiasm for Baker Hughes' stock.