FACTBOX-Main players in U.S. tobacco market

Sept 5 (Reuters) - Cigarette company Altria Group Inc (MO.N: Quote, Profile, Research, Stock Buzz) is in advanced talks to buy Skoal and Copenhagen smokeless tobacco maker UST Inc (UST.N: Quote, Profile, Research, Stock Buzz).

Buying UST would be a quick way for Altria to expand in the smokeless tobacco market as the U.S. cigarette market steadily declines. A combination would also bolster Altria against rival Reynolds American Inc (RAI.N: Quote, Profile, Research, Stock Buzz), which bought smokeless tobacco maker Conwood in 2006.

Here is a look at the main players in the U.S. cigarette and smokeless tobacco markets:

ALTRIA

* Owns Philip Morris USA, cigarette brands include Marlboro, Parliament and Virginia Slims

* U.S. cigarette market share: 51 percent

* Second-quarter shipment volume: 43.6 billion cigarettes

UST

* Owns premium smokeless tobacco brands Skoal and Copenhagen

* U.S. smokeless tobacco market share: 58 percent

* Second-quarter premium brands volume: 143.2 million cans

REYNOLDS AMERICAN INC

* Owns Camel, Pall Mall and Kool cigarette brands under R.J. Reynolds Tobacco Co

* Owns Conwood, home to the Grizzly and Kodiak smokeless tobacco brands

* Conwood smokeless tobacco market share: 27.8 percent

* R.J. Reynolds U.S. cigarette market share: 28.1 percent  Continued...