FAT Brands, the parent of Los Angeles-based burger chain Fatburger Corp. and Buffalo's, announced on its website that it plans to go public, while surveying customers of their interest in an initial public offering. "Make history today with our parent company FAT Brands," said a statement on the website. "Register your indication of interest to purchase shares in our I.P.O. by clicking below." Fatburger operates in 5 states and 18 countries, while Buffalo has locations in two states and Qatar. An IPO would come at a tough time for shares of fast-casual burger companies. Shake Shack Inc.'s stock SHAK, -3.53% has lost 6.5% year to date and shares of Habit Burger Grill parent Habit Restaurants Inc. HABT, +0.49% have tumbled 9.9%, while the S&P 500 SPX, -0.26% has climbed 10.7%.