With the free pool of IPv4 addresses empty at ARIN, they’ve setup a waiting list for unmet requests:
When an IPv4 block becomes available, the oldest waiting list request that has specified a minimum acceptable block size equal to or less than the available block will be filled and the request will be removed from the waiting list. ARIN will re-verify the organization’s justified need to make sure nothing with regard to the organization’s justification for resources has materially changed since the original request was approved.
Someone has been holding out for a /15 ( though they’ll accept a /16 ) since 10 Jul 2015.