Check out which companies are making headlines before the bell on Monday:
Berkshire Hathaway - Berkshire reported fourth-quarter profit of $1,704 per share, below Street estimates of $1,755, and Warren Buffett called the company's 2012 performance "subpar" in his annual letter to shareholders.
(Read More: Buffett Still Buying Stocks, Sees 'Good Value')
Transocean - Transocean reported fourth-quarter profit of $0.91 per share, excluding certain items, nine cents above estimates, with revenue essentially in line with consensus. The offshore drilling contractor saw its so-called revenue efficiency rise to 94.7 percent compared to 91.8 percent a year earlier.
Las Vegas Sands - Las Vegas Sands is disputing reports out late Friday that it likely violated the Foreign Corrupt Practices Act. The casino operator said that its audit committee found likely violations of accounting provisions, which could mean just a single or a handful of incorrectly recorded transactions. Las Vegas Sands is particularly upset with a New York Times headline that said "Casino Says It Likely Cheated," calling it uninformed and misleading reporting.
(Read More: See the Day's Top Percentage Winners & Losers)
Yahoo - Yahoo is planning to discontinue seven of its products, including its mobile BlackBerry app. Also among the eliminated: Yahoo App Search, Yahoo Sports IQ, Yahoo Clues, and Yahoo Message Boards. Separately, Barclays is upgrading Yahoo to "overweight" from "equal weight," saying Yahoo's stakes in Alibaba and Yahoo Japan are undervalued. (CNBC has a content-sharing partnership with Yahoo's finance site.)
Anheuser-Busch InBev - The beer brewer is attacking accusations that it watered down its beer with a series of full page newspaper ads. The ad blitz is in response to a class action lawsuit that accuses the company of adding water just before bottling its beers.
Elan - The drugmaker is offering shareholders 20 percent of the royalties for the best-selling multiple sclerosis drug Tysabri, in an effort to dodge a $6.6 billion takeover bid by investment firm Royalty Pharma.
Celgene - Celgene says an experimental psoriasis drug was found to be safe and effective in a trial, which paves the way for a filing for regulatory approval during the second half of this year.
United Technologies - Company unit Pratt & Whitney has uncovered a fraudulent engine-testing scheme, according to The Wall Street Journal. That follows an investigation which began back in 2011.
MetroPCS - The mobile phone service provider is being pressured by one of its biggest investors to update its Securities and Exchange Commission filings. P. Schoenfeld Asset Management wants the company to update those fillings to reflect the earnings of T-Mobile. The Deutsche Telekom unit and MetroPCS agreed to merge last October, a deal which P. Schoenfeld has strongly criticized.
Charles Schwab - Bernstein has upgraded the discount broker's shares to "outperform" from "market perform."
Hess - The oil giant has raised its annual dividend to $1 per share from $0.40, announced a repurchase program of up to $4 billion, and said it will exit its retail business.
(Read More: See CNBC's Market Insider Blog)
—By CNBC's Peter Schacknow
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