What happens when your new material aggregates or brings together separate pieces of information?

The answer

When your new material aggregates or brings together separate pieces of information, you must consider classification by compilation (also called classification by aggregation). The rule: individual items may each be unclassified, but when they are combined, the compilation can reveal an additional association or relationship that meets the standard for classification. In that case the compiled document is classified — and must be marked and protected at the appropriate level — even though none of its parts is classified on its own.

Why the whole can exceed the parts

This is a core concept in derivative classification training (such as the DoD/IF103-style courses). A classic illustration: a phone directory entry, a project name, and a shipping schedule might each be public. But combined, they could reveal that a specific classified program is operating from a specific location on a specific date — a fact the government protects. The compilation exposes a relationship that the isolated facts did not, so the new document derives a classification even though you never copied classified source material into it.

What a derivative classifier must do

If you are creating material that aggregates information, you are expected to:

• Recognize that combining items may produce a classified compilation.
• Consult the security classification guide (SCG) or an original classification authority to determine whether the compilation is classified and at what level.
• Mark the document at the classified level the compilation warrants, including a note in the "Reason" or classification-by-compilation explanation that the classification results from the compilation, so a reader does not wrongly conclude each part is classified.
• Protect and handle the document at that classified level — storage, transmission, and access controls.

Why the simpler answers are wrong

It is tempting to think, "every piece is unclassified, so the document is unclassified." That is exactly the mistake this rule guards against — classification depends on what the combination reveals, not just on the status of each part. It is equally wrong to assume aggregation always produces classified material; it only does so when the compiled whole reveals something meeting the classification standard, which is why a classifier must evaluate it rather than guess.

The bigger picture

Derivative classification is the act of incorporating, paraphrasing, restating, or generating in new form information already classified, and marking the new material consistent with its source or a classification guide. Classification by compilation is a special case where the act of assembling unclassified pieces creates classified information. The safe practice: whenever you aggregate data, pause and check the classification guidance before releasing it.