Agreement with London-based Lemon Pepper calls for 100 restaurants

Company, franchisees withdraw from underperforming market amid sales problems

Same-store sales fall 2.5 percent at company-owned restaurants

CEO Charles Morrison says customers are responding well to a test in Las Vegas

Giveaway coupled with cold weather results in same-store sales decline

COO Glenn Lunde promoted to president

Healthful fast-casual chain generates strong same-store sales

Result marks first quarterly decline since popular burger chain’s IPO

Company warns that challenging environment will continue

Balmoral Funds and Gala Capital acquire Dallas-based burger brand