Wall St. Watchdog reveals information about companies for which stock analysts upgraded shares in the Basic Materials sector for the week ending December 23rd, 2011.

Ultra Petroleum (NYSE:UPL): Canaccord Genuity upgraded its rating on this company from Hold to Buy and changed its price target from $50 to $53 on Dec 21st. The shares recently traded at $30.95, up $1.29, or 4.35% since the analyst’s rating. About the company: Ultra Petroleum Corp. is a natural gas exploration and production company focused on the Green River Basin of Wyoming in the United States. The Company also explores for oil and gas in China. Get the most recent company news and stock data here >>

Potash (NYSE:POT): RBC Capital Mkts upgraded its rating on this company from Sector Perform to Outperform and changed its price target from $58 to $50 on Dec 22nd. The shares recently traded at $42.57, down $0.06, or 0.14% since the analyst’s rating. About the company: Potash Corporation of Saskatchewan Inc. produces potash, phosphate, and nitrogen to the agricultural and industrial industries worldwide. The Company conducts operations in Canada, Chile, the United States, Brazil, and Trinidad. Get the most recent company news and stock data here >>

Bill Barrett (NYSE:BBG): Stifel Nicolaus upgraded its rating on this company from Hold to Buy and changed its price target to $43 on Dec 22nd. The shares recently traded at $34.88, down $0.13, or 0.37% since the analyst’s rating. About the company: Bill Barrett Corporation is an independent oil and gas company focused on natural gas exploration and development in the Rocky Mountain region of the United States. Get the most recent company news and stock data here >>

(Note: Selected financial data are sourced from Briefing.com via the Wall St. Journal. All data are assumed to be accurate.)

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