51.86—What encumbrances require the approval of the Director?
The concessioner may not encumber, pledge, mortgage or otherwise provide as a security interest for any purpose (such transactions collectively referred to as “encumbrances” for purposes of this part), without the prior written approval of the Director, any of the following:
(b)
Any rights to operate under or manage performance under a concession contract as a subconcessioner or otherwise;