Early Movers: SIRI, AA, IBM, DELL, MSFT & More

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

These stocks are moving before the bell on Tuesday:

Harris Teeter The supermarket operator will be acquired by Kroger for $49.38 per share in cash, or about $2.5 billion. Harris Teeter had announced in January that it was considering strategic alternatives.

Sirius XM Radio — The satellite radio operator is raising its full year guidance for subscriber additions to 1.5 million from its prior 1.4 million. It also announced 715,000 net new subscribers for the second quarter, putting it past the 25 million mark.

Alcoa —The aluminum producer kicked off earnings season by reporting second quarter profit of 7 cents per share, one cent above estimates, with revenues essentially in line. Alcoa is still dealing with weak aluminum prices, which were down four percent from a year earlier.

IBM The stock has been downgraded by Goldman Sachs to "neutral" from "buy", with Goldman saying it sees pressure on IBM's growth markets and higher margin revenue streams.

WD-40 —The maker of the popular lubricant earned 66 cents per share for its third quarter, ten cents above estimates, with revenues also beating consensus. The company also raised its fiscal 2013 guidance on strong sales.

Dell — Despite the recommendations of proxy firms like ISS and Egan-Jones, major shareholder Pzena Investment Management plans to vote against the buyout offer from Michael Dell and Silver Lake Partners. Pzena calls that bid "unreasonable" and favors the alternative proposal being put forth by investor Carl Icahn.

Intuitive Surgical —The maker of robotic surgical systems is forecasting second quarter sales that are below Wall Street estimates, citing fewer hospital admissions and economic pressures prompting hospitals to hold off on purchasing new equipment. The company also points to more conservative payment decisions by insurance companies.

Barnes & Noble —William Lynch has resigned as chief executive officer after three years in that job. A successor hasn't yet been named, and the book seller is now reviewing its overall strategy.

Royal Dutch Shell —The oil company named Ben van Beurden as its new chief executive, replacing Peter Voser. The choice came as a surprise to analysts, who had not considered van Beurden a possible candidate. Voser announced two months ago that he would depart earlier than planned.

Quest Diagnostics —Morgan Stanley downgraded the stock to "Equal weight" from "Underweight".

Microsoft — All Things D reports an announcement on Microsoft's long-anticipated restructuring will happen on Thursday.

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

—By CNBC's Peter Schacknow

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