The markets opened flat with the Dow adding 3 points to 12,446 while Nasdaq eased a point to 2812. Greece's downgrade further into junk territory tempered enthusiasm for Facebook's initial public offering.

On the upside

Technology blog AllThingsD reported that Yahoo (Nasdaq: YHOO) was finalizing details of plan to sell nearly half of its stake in Alibaba Group for approximately $7 billion.

CLSA Asia-Pacific Markets upgraded Salesforce.com (NYSE: CRM) to a Buy rating and lifted its price target to $180 from $160.

First quarter earnings for Foot Locker (NYSE: FL) soared to surpass analysts expectations as revenue rose.

On the downside

Autodesk (Nasdaq: ADSK) reported higher first quarter earnings and revenue but warned that second revenue will fall short of analyst expectations.

Coventry Health will not cover the cost of Sequenom's (Nasdaq: SQNM) Down syndrome test MaterniT21 as originally announced on May 9.

Investors locked in profits on Renren (NYSE: RENN).

In the broad market, advancing issues outpaced decliners by a margin of more than 10 to 9 on the NYSE while decliners barely edged out advancers by a slim margin on Nasdaq. The Russell 2000 which tracks small cap stocks edged up a fraction to 755.