Oakley is an American brand that’s been designed and engineered in California since the company’s inception in 1975. For a long time Oakley manufactured all its products in the USA, many at the company’s headquarters in Foothill Ranch, California, which is famous for its architecture, (see the photo below).
Back then, an identifying mark of genuine Oakleys was a “Made in USA” stamp etched on the inside of the temple. But in 2007, when Oakley was bought by Luxottica, some eyewear components and finished products started being manufactured in other facilities in China and around the world.
Now it depends on which style of glasses you purchase., Some Oakley glasses are still made in the USA—like some special editions and most of the standard issue (military) editions. Sometimes the components are made overseas and assembled in the USA. But Oakleys are no longer exclusively made in the USA, so not having “Made in USA” designation does not indicate that the glasses are fake.