Shake Shack tracks higher amid chatter over a McDonald's buyout

• Shake Shack (SHAK +0.9%) is on an upswing this week with some ungrounded rumors still circulating on McDonald's (MCD +1%) having an interest in acquiring the high-growth burger chain.
• Shares of SHAK are up 4% on the week and are making a bid to reach $40 for the first time since March.
• Industry watcher Restaurant News summarizes the case for McDonald's to add the Shake Shack business, but also calls a deal "highly unlikely."