USCIB: 4.2/37 llkNBLE VIA 8CMIN'f Blh\NfH!if..S ON:t.Y 

19 January 1955 

'J:OP il!:S~ 

Ml!MORANDUM FOR THE MEMBERS OF USCIB: 

Subject: USCIB Directive No. 6. 

Reference: USCIB 4.2/32, dated 17 December 1954. 

1. The revision of USCIB Directive No. 6, forwarded as an enclosure 

with the reference, has now been approved by USCIB. 

2. Enclosed for your information is a copy of the revised directive 

as finally approved. 

3. Additional copies of this directive are obtainable from this 

office on request. 

USCIB: 4. 2/37 
USCIB DIRECTIVE NUMBER 6 (CIBD # 6) 

(APPROVED BY USCIB ON 11 Mar 49) 

(Revised by USCIB on 13 Jan 55) 

INSTRUCTIONS FOR THE PROTECTION OF 

COMINT CODEWORDS 

l. Regulations for the dissemination, handling, and saf eguard.ing 

of COMINT will: 

a. Refer to the CClUNT codewords only generically, and will 

not list specific codewords. These regulations will be so drafted that 

they will not themselves require designation by a CD.MINT codeword, and 

will thus avoid such designation. 

b. Clearly provide for the continuous safeguarding and 

security of superseded Co.MINT codewords, and material covered by them, 

as well as of current ones. 

2. Knowledge of specific current and non-current COMINT codewords will be disseminated by each member org!:l.nization in accordance 

with the basic security regulations and to the extent necessary to 

insure compliance with these regulations, and in a manner appropriate 

to that organization's administrative arrangements and procedures. 

,3. When used as such, codewords for Category III COMINT (and 

sub-categories thereof) are classified TOP SECRET. These codewords 

and their implications shall not be made known to non-indoctrinated 

persons, nor shall these codewords be used in their codeword sense 

in the presence of non-indoctrinated persons. Paper stocks and 

rubber stamps bearing such codewords must be treated accordingly. 

TOP SECRET 
IJ 

'f01' SEC!E':F 

4. When used as such, codewords for Category II COJ.UNT (and 

sub-categories thereof) are classified SECRET. These codew,ords and 

their implications shall not be made known to non-indoctrinated. 

persons, nor shall these codewords be used in their codeword sense 

in the presence of non-indoctrinated persons. Paper stocks and 

rubber stamps bearing such codewords must be treated accordingly. 

5. Codeword stamps for categories and sub-categories of CCMINT 

ma:y be manufactured integral with stamps bearing appropriate classification when such work can be accomplished by indoctrinated 

personnel. Similarly, paper stocks bearing a codeword in association with a classification must be printed by indoctrinated 

personnel. 

6. Codewords shall normally be replaced every two years unless 

positive security advantages will be obtained by an earlier change. 

In such cases, a new period of two years shall be in effect from the 

date of the change. 

7. Prior to the effective date of a change ih codewords, extreme 

care should be exercised to insure that the new word is made known 

only to the minimum number of personnel consistent with operational 

necessity. In no case should the word be divulged to personnel who 

are expected to be debriefed prior to the effective date of the ~ha..~ge. 

Approved by USCIB on 11 Mar 49 

Revised by USCIB on 13 Jan 55 

- 2 -

TOP S8CRBT 

CIBD # 6 (Revised)