I have both sets (4 each) right now of those Volther chairs with the upholstered seats but I have also had a set in the past that was paper corded and they were marked made in Malaysia so I am pretty sure that someone has produced knockoffs there. They were made the same way however with the double hex bolt on each leg. Not all of the chairs was the mark easily visible, a couple of them were under the plate where those hex bolts were.
Not all of the SE Asian production during the 70's should be lumped under "knockoffs". A few Danish companies set up production operations there and made licensed pieces. I'm not saying that the quality and current value would be the same as Danish-made pieces; only that they would not be knockoffs.
Here is an interesting set of Koefoed Eva chairs I saw a few years ago, in which it appears the teak frames were made in Thailand, but the final chair assembled (and possibly upholstered) in Denmark, allowing it to have a "Made in Denmark" designation. I must give credit to the seller for leaving those Thailand labels on, as it would be oh so tempting to peel them off.
I also believe there is some type of connection between either Uldum or Johannes Andersen and d-Scan (from Singapore), as most of d-Scan's chairs were made earlier by Uldum and designed by JA. It seems logical that there was some type of licensing agreement in place to shift production from Denmark to Singapore for economic reasons (rather than so blatant knockoffs of this particular Danish designer/maker), but I have not found any evidence so far that would confirm that.
I remember a company called Danish Overseas Furniture which was set up in the 70s and produced in the Philippines. Erling Torvits drew for them at the end of his carreer. I think moving to Asia was a quite popular way for Danish entrepreneurs in the 70s to cut production costs. But in many cases it didn't really work out. The demand for teak furniture continued to decline. And the problem with Danish Overseas Furniture for instance was that the Philippine government banned large-scale logging in the mid 70s, so the project came to an end.
"People buy a chair, and they don't really care who designed it." (Arne Jacobsen)
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