Robert Morley, an associate professor at the Washington University, sued Square co-founders Jim McKelvey earlier today for patent infringement and fraud. According to reports from the St. Louis Post Dispatch, Morley has a long-standing dispute with Square from years ago.

In 2010, Square's co-founders sued Morley's firm, REM Holdings 3 LLC for wrongly leaving off McKelvey in a patent for the card reader device. The case is still pending as the US Patent and Trade Office is still reviewing other patents related to the technology being used by Square, the report explained.

Square is a small device made of plastic that can be attached to devices such iPhones and tablets. The device processes credit card payments to facilitate easier payments for small businesses. According to financial analysts and the press, the San Francisco-based firm has a strong potential for an initial public offering (IPO), the report stated.

Based on the 2010 lawsuit, McKelvey first thought about making a credit card reader. He then reached out to Dorsey, who contacted Morley to develop a prototype of the said device. Morley, however, is alleging that the card reader was his sole idea and therefore should be recognized as one of Square's co-founders, VentureBeat reported.