A messy spinoff helped push down the value of automotive supplier BorgWarner's (NYSE: BWA) stock over the past few trading days. According to data compiled by S&P Global Market Intelligence, its price was down by slightly more than 8% week to date as of early Friday morning. BorgWarner kicked off the week with that spinoff; its onetime fuel systems and aftermarket business is now a separate, publicly traded company known as Phinea.