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Stands for Hubbard Communications Office Bulletin. These are red ink on white paper references written by L. Ron Hubbard. They cover the subjects of auditing, training to be an auditor, and how to supervise preclear cases so they receive the auditing best suited to help them go up the Grade Chart.

L. Ron Hubbard wrote 1000’s of HCOBs. The bulk of them are contained in an encyclopledic-like set of chronological volumes called Technical Volumes. If a person went to a Scientology course room to train as an auditor, each of the course packs would contain HCOBs related to the type of auditing they were learning.

Sometimes at the end of definitions in this glossary, you will see an HCOB being referenced. This reference includes the date of release. Dates are written day, month, year. For example if it said HCOB 5 Apr 69, that means the reference referred to was written on the 5th of April, 1969.

A few other helpful things to know:

  • If Hubbard wrote more than one HCOB in a day, the reference will be followed by a roman numeral to differentiate if from other HCOBs on the same date. For example, HCOB 5 Apr 69 II would be the second HCOB issued on that date.
  • If an HCOB was revised for some reason, perhaps to correct a typo or other error, or to modify a reference after Ron made a new discovery, then there will be an R at the end. If a second revision occurred, it becomes RA. If a third revision, then it becomes RB. For example, if you had HCOB 5 Apr 69RC III, that means the original HCOB came out on Apr 5th, 1969. Over time it was revised four times. And it was the third HCOB issued on that original date.

Some other reference types: HCOPL, Tape Lecture, BTB, BPL.

(HCOPL 24 Sept 70R)

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