The bootleg record label, Trade Mark of Quality, created some of the first and best-known recordings from the 1960s and 70s of popular music. From Great White Wonder and Live'r Than You'll Ever Be to Blueberry Hill, some of the best recordings came from a bootlegger known only as Pigman.

We talked with Ralph Sutherland and Harold Sherrick, the authors of the definitive history and catalogue of the TMQ label. A Pig's Tale is available from Genius Books.

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