Set in lower case mark

A struck-through capital with a marginal note.

Also known as: Downcase mark, lc mark

Engineering & technicalEveryday & digitalStandard profile

Meanings

The proof correction mark instructing that a capital be changed to lower case.

Officially standardisedVerified fact
Instructs that a capital letter be changed to lower case.
Contexts: Technical drawing
Officially standardisedVerified fact
Uses a ringed letter code in the margin, the ring marking the letters as an instruction rather than as matter to be set.
Contexts: Technical drawing

A stroke drawn through the capital letter, answered in the margin by a short letter code enclosed in a ring.

IdentityHigh confidence: High confidence because the identity is defined by a current official standard.
Historical originModerate confidence: Moderate confidence because the historical origin is documented in encyclopedic references, but early or supporting evidence is limited, but the regional or cultural match to this specific claim is not precise.
Current useHigh confidence: High confidence because the current use is defined by a current official standard.
Visual matchHigh confidence: High confidence because the visual match is documented in encyclopedic references.

BS 5261 — Copy preparation and proof correction
British Standards Institution · retrieved 2026-08-21
The British Standard defining proof-correction marks and their marginal counterparts. Paywalled, so records describe the marks as documented in secondary summaries of the standard rather than quoting its text. Authoritative for British practice; American convention differs in several marks.
The Chicago Manual of Style
University of Chicago Press · retrieved 2026-08-21
The principal American style authority, including its table of proofreaders' marks. Authoritative for American publishing convention; British practice under BS 5261 differs in several marks and in the use of colour.

Last reviewed 2026-08-24

Meanings

The proof correction mark instructing that a capital be changed to lower case.

Officially standardisedVerified fact

Instructs that a capital letter be changed to lower case.

Officially standardisedVerified fact

Uses a ringed letter code in the margin, the ring marking the letters as an instruction rather than as matter to be set.

Confidence

IdentityHigh confidence: High confidence because the identity is defined by a current official standard.
Historical originModerate confidence: Moderate confidence because the historical origin is documented in encyclopedic references, but early or supporting evidence is limited, but the regional or cultural match to this specific claim is not precise.
Current useHigh confidence: High confidence because the current use is defined by a current official standard.
Visual matchHigh confidence: High confidence because the visual match is documented in encyclopedic references.

Sources

BS 5261 — Copy preparation and proof correction
British Standards Institution · retrieved 2026-08-21
The British Standard defining proof-correction marks and their marginal counterparts. Paywalled, so records describe the marks as documented in secondary summaries of the standard rather than quoting its text. Authoritative for British practice; American convention differs in several marks.
The Chicago Manual of Style
University of Chicago Press · retrieved 2026-08-21
The principal American style authority, including its table of proofreaders' marks. Authoritative for American publishing convention; British practice under BS 5261 differs in several marks and in the use of colour.

Last reviewed 2026-08-24