AssetMetrix Research Labs said 22 percent of the 600,000 corporate PCs it surveyed that run Office with Access must be upgraded with Office 2003 SP2 and a special patch.
Microsoft previously said the number of users affected by the upgrade was a "small percentage."
Microsoft told customers using Microsoft Office Professional 2003 and Microsoft Access 2003 that they must install Office 2003 SP2 and a special patch to be in compliance.
AssetMetrix found that 68 percent of Office 2003 and Office XP installs contained the offending Access code.
"This is quite a significant amount of affected installations," said Jeff Campbell, CEO of AssetMetrix, whose Ottawa, Canada, company uses an analytics engine to sift through PC data.
However, Microsoft said in a statement the court ruling only affects customers in the process of new installations and any future installations of the affected products.
"The AssetMetrix report and tools only focus on existing installations and are not relevant to this patent case since this requirement is for new installations, not existing ones," said Sunny Jensen Charlebois, a senior product manager at Microsoft.
"Our customers with existing installations of the affected products are covered by our indemnification policy; and we are providing customers with resources to help them install Office 2003 SP2 or the Office XP/Access 2002 patch or they can choose not to install Access."