There are three types of Chief Counsel Bulletins available on IRS.gov:
Collection, Bankruptcy and Summonses (CBS) Bulletins
The Collection, Bankruptcy and Summonses (CBS) Bulletin (previously titled the General Litigation Bulletin) contains summaries of recent court cases of interest to anyone handling general litigation issues, plus summaries of Chief Counsel Advice issued by CBS and available for public inspection under I.R.C. section 6110.
Criminal Tax Bulletins
Criminal Tax Bulletins are compilations of recent cases pertaining to criminal tax matters as published by the Office of the Division Counsel/Associate Chief Counsel (Criminal Tax).
Disclosure Litigation Bulletins
Disclosure Litigation Bulletins were published by the Office of the Assistant Chief Counsel (Disclosure & Privacy Law), providing litigation developments and discussion of other disclosure-related issues that arise primarily under I.R.C. 6103, the Freedom of Information Act, and the Privacy Act of 1974, as these issues relate to Internal Revenue Service and Chief Counsel operations.