SavvySoft, a New York City ISV, says Microsoft is threatening to charge it with trademark infringement for calling its software TurboExcel.

SavvySoft says that when it called Microsoft in the spring to see if there was any problem about calling its stuff TurboExcel it was referred to a Web page listing Microsoft's trademarks.

Excel wasn't on the list and SavvySoft only found out later that Microsoft had only applied for the trademark this past April, 19 years after it started selling Excel. Microsoft doesn't have the trademark yet.

SavvySoft CEO Rich Tanenbaum says he doesn't know why Microsoft has singled TurboExcel out unless it's the fact that it can convert Excel models into C++ code that runs on Linux as well as Windows.

"If all the business logic written in Excel moves to C++, it's the death knell for Microsoft's spreadsheet monopoly," he said. Otherwise, he points out that Microsoft's own web site offers downloads of over a dozen products with Excel in their name. He claims that by not protecting its rights, Microsoft has already lost trademark protection.

Besides making Excel portable to Linux, SavvySoft says TurboExcel speeds up Excel spreadsheets as much as 300 times and secures and protects proprietary spreadsheet methodologies.

Tanenbaum, who's got to figure whether to spend $500,000 defending the TurboExcel name or $100,000 rebranding it, said that by using Excel to write computer programs in C++, Excel becomes a programming tool, which could help Microsoft sell more Excel.