copyright?

[HVizier]

both designs come to the double rim via entirely different means, thus making the resemblance only in aesthetics (which even then isnt very similar)

[yoyofactoryben]

Designs evolve.

YoYoFactory popularized stepped rim yoyos, for both style and function. Rather than credit some people chose to say it was done before (ie Henrys Lizard).

Now stepped rim yoyos feature on many many brands.

Its evolution.

and for those stuck in the past check out a Losi Cherry Bomb.