The leader in measuring the digital world, comScore on Tuesday (May 12, 2009) released study of online Ad publishers based on March 2009 data from the comScore Ad Metrix service.

According to the comScore study, Yahoo! Sites ranked as the top display ad publisher and AT&T ranked as the top display advertiser. Yahoo! Sites ranked as the top U. S. display ad publisher in March with 42.8 billion ad views (13.2 percent market share) reaching 139 million people online. Fox Interactive Media ranked second with 31.4 billion ad views (9.7 percent), while Facebook. com captured the third spot with 24.8 billion ad views (7.7 percent).

The comScore study found that AT&T ranked as the top display advertiser in March with nearly 6 billion ad views (1.8 percent market share), which reached 147 million people online. A significant theme across AT&T's display ad campaigns in March was the promotion of free camera phones, including the Sony Ericsson W350. Other top display advertisers included Verizon with 5.7 billion ad views (1.8 percent share), Vonage with 4.3 billion ad views (1.3 percent) and Scottrade with 4 billion ad views (1.2 percent).