Sec.  52.20   Thousands-block number pooling.

   (a) Definition. Thousands-block number pooling is a process by which the
   10,000  numbers  in a central office code (NXX) are separated into ten
   sequential blocks of 1,000 numbers each (thousands-blocks), and allocated
   separately within a rate center.

   (b)  General  requirements.  Pursuant  to the Commission's adoption of
   thousands-block number pooling as a mandatory nationwide numbering resource
   optimization  strategy,  all  carriers,  except  those exempted by the
   Commission, must participate in thousands-block number pooling where it is
   implemented and in accordance with the national thousands-block number
   pooling framework and implementation schedule established by the Commission.

   (c) Donation of thousands-blocks. (1) All service providers required to
   participate in thousands-block number pooling shall donate thousands-blocks
   with ten percent or less contamination to the thousands-block number pool
   for the rate center within which the numbering resources are assigned.

   (2) All service providers required to participate in thousands-block number
   pooling shall be allowed to retain at least one thousands-block per rate
   center, even if the thousands-block is ten percent or less contaminated, as
   an initial block or footprint block.

   (d) Thousands-Block Pooling Administrator. (1) The Pooling Administrator
   shall be a non-governmental entity that is impartial and not aligned with
   any particular telecommunication industry segment, and shall comply with the
   same neutrality requirements that the NANPA is subject to under this part.

   (2)  The Pooling Administrator shall maintain no more than a six-month
   inventory of telephone numbers in each thousands-block number pool.

   [ 65 FR 37709 , June 16, 2000, as amended at  66 FR 9532 , Feb. 8, 2001;  68 FR 43009 , July 21, 2003]