In the NCAA, a school's brand is of paramount importance. 

From the font, to the colors, to the mascot, to the logo, each school has trademarks on unique aspects of their identity. By holding these trademarks, the schools are able to sell their unique merchandise and license to only those they see fit.  

Since these logos and images are so important for making money, the schools will fight hard to keep their identity. 

When Ohio State filed a patent for the "OSU" lettering on  apparel and sportswear, Oklahoma State was not happy. They too have a patent on the "OSU" logo and have been using it as part of a  "concurrent agreement" with Ohio State and Oregon State.

Both the schools have patents on the "OSU" lettering, and these apply differently in the states surrounding each school. Iowa is even split by the county on which patent they recognize. 

Oklahoma State has formally opposed Ohio State's application (which was filed back in February), and has until the end of August to formally make their objection. Ideally, the schools can work out an agreement to continue the joint usage of the letters. 

But since this is all about money, it's possible that an amicable end to this may be far away.