Conversation so far:
when did baskin robbins and dunkin donuts merge
In 1990, Allied Lyons, which owned Baskin Robins, acquired Dunkin' Donuts and Mister Donut.
where is the headquarters of dunkin' brands
Dunkin' Brands is headquartered in Canton, Massachusetts.

Question: what is the stock symbol
Self-contained rewrite: what is the stock symbol for dunkin’ brands