Chief Counsel Advice is part of the Legal Advice Program of the IRS.
Chief Counsel Advice (CCA) are legal advisories written by the Chief Counsel's National Office to advise IRS personnel at all stages of case development. They convey legal interpretations or positions of the Office of Chief Counsel regarding existing or former revenue provisions.
"Legal advice that constitutes CCA and its background file documents are made available for public inspection in accordance with IRC § 6110. Nontaxpayer specific CCA must be made available for public inspection within 60 days after the date on which it is signed. Taxpayer specific CCA generally must be made available for public inspection 75 to 90 days after the Service provides notice of intention to disclose to the taxpayer to whom the advice pertains. Background file documents are made available upon written request" I.R.M. 220.127.116.11.
Lexis Advance and Westlaw provides access to Chief Counsel Advice from 1999 - present. The scope notes indicate that some material is redacted before public release. Generally,the information deleted includes names, addresses, and other identifying details. This is in keeping with the Internal Revenue Manual rules for releasing Chief Counsel Advice to the public.