Cognex, Entropic, Jabil, LaSalle, Walgreen: U.S. Equity Movers

Shares of the following companies are having unusual moves in U.S. trading. Stock symbols are in parentheses, and prices are as of 9:45 a.m.

Index changes: Rackspace Hosting Inc. (RAX US) rose 2.7 percent to $24.99, Watsco Inc. (WSO US) gained 0.7 percent to $56.26 and Riverbed Technology Inc. (RVBD US) advanced 1.8 percent to $45.02 after Standard & Poor’s said they will replace AmeriCredit Corp. (ACF US), Hewitt Associates Inc. (HEW US) and NBTY Inc. (NTY US), in the Standard & Poor’s MidCap 400 index.

Super Micro Computer Inc. (SMCI US), which will replace Watsco in the S&P SmallCap 600 index, climbed 5.4 percent to $10.36.

American Capital Agency Corp. (AGNC US) fell 6.8 percent to $26.10. The real estate investment trust said it plans to offer 10 million shares. Additional stock can dilute the value of existing shares.

Cognex Corp. (CGNX US) rose 6.8 percent to $24.45. The maker of mechanical vision systems that monitor manufacturing raised its forecast for third quarter revenue to as much as $76 million. Analysts on average estimated $66.7 million, according to a Bloomberg survey.

Entropic Communications Inc. (ENTR US) slid 5.1 percent to $9.30. The designer of digital home networking semiconductors said it would offer 10 million shares.

Jabil Circuit Inc. (JBL US) declined 3.6 percent to $13.39. The St. Petersburg, Florida-based electronics manufacturer forecast first-quarter sales of $4 billion at most, trailing the average analyst estimate of $4.08 billion.

LaSalle Hotel Properties (LHO US) fell 1.2 percent to $23.18. The real estate investment trust focused on luxury and upscale full-service hotels said Chief Financial Officer Hans S. Weger will leave the company no later than Feb. 28, 2011.

Newmont Mining Corp. (NEM US) lost 1.7 percent to $61.60. The largest U.S. gold producer was cut to “hold” from “buy” at Stifel Nicolaus & Co. The share-price estimate, which was $80, was eliminated.

Walgreen Co. (WAG US) jumped 9.9 percent to $33.34. The largest U.S. drugstore chain had fourth-quarter adjusted earnings excluding Duane Reade of 53 cents a share. The average analyst estimate in a Bloomberg survey was 44 cents.

To contact the reporter on this story: Tara Lachapelle in New York at tlachapelle@bloomberg.net Lu Wang in New York at lwang8@bloomberg.net

To contact the editor responsible for this story: Nick Baker at nbaker7@bloomberg.net.