It is buying the ads "to refocus the current debate over competition onto the central principle that the company is standing up for--the ability of every American company to continually innovate by integrating new technologies and ideas into its products," the company said in a statement.
"We believe the marketplace should determine what innovations consumers want," the text of the ads reads. "At Microsoft, the freedom to innovate for our customers is more than just a goal; it is a principle worth standing up for."
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"We want to begin a discussion with the American public and PC users in particular about the principle we are fighting for," noted Microsoft chief operating officer Bob Herbold. "Some of our competitors have been working to hobble competition."
Redmond rivals such as Netscape Communications and Sun Microsystems have charged publicly and before members of Congress that Microsoft unfairly wields clout in the market. Many consumers say they are concerned about Microsoft's business practices as well.
Both the states and the DOJ are investigating Microsoft for alleged antitrust practices. Microsoft denies any wrongdoing.