Gruma, S.A.B. de C.V., known as Gruma, is a Mexican multinational corn flour (masa) and tortilla manufacturing company headquartered in San Pedro, near Monterrey, Nuevo León, Mexico. 

It is the largest corn flour and tortilla manufacturer in the world. Its brand names include Mission Foods (Misión in Mexico), Maseca, and Guerrero. Gruma reported revenues of US$ 3.8 billion for 2014.

It operates more than 79 plants worldwide, mainly in Mexico, the United States and Europe, and employs approximately 18,000 people. 

Gruma produces and commercializes corn flour and tortillas in the United States, Europe, and China. In the United States, Gruma Corporation is headquartered in Irving, Texas.

Gruma Corporation in China is based in Shanghai, and made it the first tortilla producer in that country. It has a production capacity of 15,000 tonnes (14,800 long tons; 16,500 short tons) of wheat tortillas, 7,000 tonnes (6,890 long tons; 7,720 short tons) of corn tortillas and 6,000 tonnes (5,910 long tons; 6,610 short tons) of snacks.

In Asia, the company also has distributors in Japan, South Korea, Singapore, Hong Kong, Thailand, Philippines and Taiwan.

It is listed on the Mexican Stock Exchange since 1994, and it had a NYSE listing through ADRs from 1998 to September 2015. It is a constituent of the IPC, the main benchmark index of Mexican stocks.

According to en.wikipedia