Medicare General Information, Eligibility and Entitlement Manual (Pub. 100-01), Ch. 1 § 40.1
Assignment of A/B MAC (A) and (HHH)
Length: 34 wordsOfficial source
40.1 - Assignment of A/B MAC (A) and (HHH)
(Rev. )
CMS assigns MACs based upon jurisdictions as described in:
http://www.cms.gov/Medicare/Medicare-Contracting/Medicare-Administrative-
Contractors/MACJurisdictions.html
There are no alternate selections permitted, effective with the implementation of MACs.