Fixed! I just unchecked "Disable Partial alpha" on the Octane Camera tag. That did it. Thanks for your time.

Hi! We just upgraded to Octane 3.0 C4D Pluging. I was testing scene with same settings that was working with 2.2 but now with 3.0 we are getting a black jagged edge con the alpha. And it is not usable for us. Please see the attachment.

Octane 2.25 (Good edge)
works.jpg

Octane 3 (black jagged ...