Great thread. I just picked up a a Sigma 12-string. Has a paper label that says "DM12-2" and it's made in korea and the "sigma 1970" in the martin script logo. Also has a sticker on the back of the headstock that says "made in Korea" so I guess it's definately not a Japan model.... I haven't been able to find much info about it though. One site says the model was only produced from '87-'93, but I've only found one source that says that, and I thought that the Korean models had Martin model numbers, and not the old japanese 2, 3, 5 etc. grading system. Sounds great though, and it's in fabulous condition. Even that sticker on the headstock isn't frayed or anything ;-) I'm happy with it, don't really care much about it's value or anything, it's a keeper, but a bit of history would be nice. Anyone have any info?