McDonald’s was once a multibrand company. In 1998 the Oak Brook, Ill.-based firm invested in Chipotle Mexican Grill, a fast-casual chain with just 16 locations. By 2005 that number had climbed to 500. In January 2006 Chipotle made an initial public offering, which was well-received. Its stock price rose 100 percent on its opening day, marking the best IPO in six years.
Later that year, as part of a plan to focus on its hamburger chain, McDonald’s fully divested its i