What does “runout groove” mean?

What it means

The runout groove, also called the deadwax, is the smooth, ungrooved area situated between the final music groove and the center label of a vinyl record. This area contains etched or stamped information. This information is not part of the music but serves as manufacturing data. It typically includes matrix numbers (identifying the specific lacquer cut), engineer initials (indicating who mastered the record), and pressing plant codes (identifying where and when it was pressed). For the reseller or collector, these markings are primary identifiers. They allow for precise cataloging, distinguishing between original pressings, early test pressings, and later reissues.

What it does to price

The presence of specific, desirable runout information directly correlates with value. A clear, original matrix number corresponding to a known sought-after pressing can increase value by 2x to 5x compared to an unmarked or generic reissue. Conversely, smudged, heavily worn, or entirely absent markings can reduce perceived value by 10-20%. A specific, rare matrix number that confirms a first pressing can easily add $30–$100+ to the asking price over a standard copy.

How to spot it

The tell-tale signs are the fine, hand-etched or machine-stamped alphanumeric codes in the deadwax. Look for specific combinations of letters and numbers. Some pressings use distinct stampers or lacquer identifiers that are unique to a specific pressing run. If a seller claims a specific variant but the runout groove shows generic or incorrect numbering, it is likely a bootleg or later pressing. Sellers must provide high-resolution, well-lit photos focused exclusively on the runout area for verification.

Buying smart

Paying a premium for a record based on its runout groove is justified when the matrix numbers definitively prove an early, highly desirable pressing (e.g., a first pressing from a known small-run factory). It is not worth the premium if the markings are vague, heavily obscured by dust, or if the claimed variant cannot be cross-referenced with established collector databases. A fair deal requires the listed price to reflect the verifiable rarity indicated by the runout data.

Selling smart

Documenting the runout groove is mandatory for maximizing sale price. A listing that clearly photographs the matrix numbers and labels them (e.g., "Matrix: A-1/B-1") immediately signals to knowledgeable buyers that the record has been vetted. The single most effective element is a close-up, focused photo of the deadwax. This visual proof transforms the listing from a general sale into a specific, authenticated artifact sale, commanding a higher price point.