How to Authenticate a Frank Miller Signature

Miller’s signature is generally straightforward to authenticate due to his consistent signing style and the large body of genuine exemplars available for comparison.

Genuine Signature Characteristics

Miller signs with a confident, bold hand. His full signature — “Frank Miller” — is usually clear and legible. When adding sketches, his linework shows the same confident, high-contrast style that characterizes his published work. Genuine Miller sketches, even quick convention drawings, demonstrate professional skill and economy of line.

Sketch Authentication

Signed-with-sketch copies command higher values, creating incentive for forgery. Genuine Miller sketches are characterized by:

• Confident, unbroken linework
• Professional proportions and composition even in quick drawings
• Ink consistency with the signature
• Subject matter appropriate to Miller’s style (Batman, noir characters, abstract marks)

Red Flags

• Tentative or scratchy linework in sketches (suggests non-professional hand)
• Signatures that don’t match known Miller exemplars in proportion or style
• Copies claiming convention signing provenance without supporting documentation