We extend Williamson's (1973, 1987) transaction economics research to leased assets to help explain why some assets are acquired by capital lease and the use of other assets is acquired by operating lease. We look for evidence that capital leases are used for higher asset specificity assets and operating leases are used for lower asset specificity assets. Specifically, we find that returns on capital lease assets exceed the returns on operating lease assets. That the nature of capital lease assets differs from operating lease assets suggests that the lease standard SFAS 13 better categorizes assets under lease. The new lease standard ASU 2016-02 allows only one category for lease assets. From this we conclude that ASU 2016-02 will potentially have an adverse effect on the relevance of lease asset accounting.