According to the patents found on google:
https://www.google.com/patents/US5662332?pg=PA17&dq=magic+the+gathering&...
https://www.google.com/patents/USRE37957?pg=PA18&dq=magic+the+gathering&...
They have been issued in 1994. A patent in US is supposed to last 20 years. So in theory, in june 2014, the WOTC Should expire right?
According to a BGG user, it would be 14 years for design pattent
"For applications filed on or after June 8, 1995, utility and plant patents are granted for a term which begins with the date of the grant and usually ends 20 years from the date you first applied for the patent subject to the payment of appropriate maintenance fees for a utility patent. There are no maintenance fees for plant patents . Design patents last 14 years from the date you are granted the patent. No maintenance fees are required for design patents.
Which would implied that the patent is alreayd expired.