I don't believe they are the exact same frames, made in the same factories, as other brands. I'm under the impression they're very similar frames, but made independently. That's my understanding, anyway, but it's not based on any specifically verifiable information.
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1964 JRJ (Bob Jackson), 1973 Wes Mason, 1974 Raleigh Gran Sport, 1986 Schwinn High Sierra, 2000ish Colian (Colin Laing), 2011 Dick Chafe, 2013 Velo Orange Pass Hunter