[Blue]

I think where the confusion lies is that Hoya is a "public" company and Tokina and Kenko are private which makes it more difficult to make the links.

Pentax’s relationship with parent company Hoya was questioned, with Mr Iue replying that “Hoya is really serious about Pentax, as it’s a well-known consumer brand, which Hoya isn’t”. Mr Iue admitted that Hoya bought Pentax predominantly for their medical division and expertise, but they did also want the camera part too. Hoya firmly denied any plans to sell the Pentax photo division to Samsung or any other company, commenting that they had only just bought the company. Similarly, Hoya aren’t planning to sell the lens-maker Tokina, which they also own, or to merge it with Pentax.

http://www.photographyblog.com/index...p_not_perfect/