Unlike Canon, Sigma is another manufacturer who has kept all its lens production in Japan. https://m.dpreview.com/articles/0773575852/making-art-inside-sigma-s

Unlike Canon, Sigma is another manufacturer who has kept all its lens production in Japan. https://m.dpreview.com/articles/0773575852/making-art-inside-sigma-s-lens-factory https://m.dpreview.com/articles/0773575852/making-art-inside... They also have a very strong job-for-life philosophy to try to retain skills and experience.