USU fans love to claim that BYU stole its use of navy blue from USU. BYU in fact used navy before debuting royal blue in the 70s.

http://www.deseretnews.com/article/865574070/Teeples-No-one-can-argue-that-changing-BYUs-colors-has-been-a-business-success.html?pg=all

The original official color of USU, on the other hand, was royal blue. They switched to navy around 20 years after declaring royal the official color:

https://library.usu.edu/specol/usuarchives/universityhistory.html