Early Movers: VOD, RMBS, AMAT, YUM & More

Market Insider | What's Shaking | Earnings to Watch | Before the Bell

Check out which companies are making headlines before the bell on Wednesday:

Vodafone – Vodafone has approached Germany's Kabel Deutschland about a possible takeover of that company. The potential transaction could also move shares of Verizon , which has said it would like to buy Vodafone's 45 percent stake in the Verizon Wireless unit.

Rambus — The company settled a patent case with South Korea's SK Hynix, which will pay the rival chipmaker $240 million. The dispute over memory chip technology dates back 13 years, but Rambus CEO Ron Black has been accelerating efforts to settle such cases, including a high profile dispute with Micron Technology.

Applied Materials — Citi has added the semiconductor equipment maker's stock to its "Top Picks Live" and upgraded it to "buy" from "neutral", saying current market conditions play to AMAT's strengths.

Yum Brands – The restaurant operator reported a 19 percent drop in China same-store sales in May, in line with expectations. China is responsible for about half the sales for Yum, the parent of the KFC, Taco Bell, and Pizza Hut restaurant chains.

Boston Beer — Goldman Sachs upgraded the beer brewer to "neutral" from "sell", saying it had underestimated the success of Boston Beer's "Angry Orchard" hard cider brand.

First Solar – The maker of solar energy equipment announced a secondary offering of 8.5 million shares, with plans to use the proceeds for general corporate purposes.

Lennar — Keefe Bruyeett & Woods upgraded the home builder's stock to "outperform" from "market perform".

Prudential Financial – Prudential announced a $1 billion stock buyback program, adding to a $1 billion program announced a year ago. Prudential has repurchased about $150 million in shares under that prior program.

Herbalife – The nutritional products maker said an online survey shows its products are used by about eight million customers in the U.S., as it counters investor Bill Ackman's charges that Herbalife is nothing more than a pyramid scheme.

Toyota — North America CEO Jim Lentz told reporters in Japan that the automaker is unlikely to regain the 17 percent U.S. market share it achieved in 2009, although he does see 14-17 percent as a realistic range.

Sprint Nextel — Proxy advisory firm ISS is recommending Sprint shareholders vote to approve an improved takeover offer from Japan's SoftBank. That bid was raised to $21.6 billion Tuesday from the prior $20.1 billion.

Wells Fargo — Atlantic Equities downgraded Wells Fargo shares to "underweight" from "neutral".

Walgreen —The drug store operator agreed to pay $80 million to settle DEA charges involving its dispensing of prescription painkillers.

Liberty Global — The company has approved a $3.5 billion stock buyback, following its acquisition of Virgin Media.

(Read More: See CNBC's Market Insider Blog)

—By CNBC's Peter Schacknow

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