From what I see, there is no mention of either Sam or Jim on the actual page: https://atomicsemi.com/

This tweet alludes to Sam being associated with Atomic Semi https://twitter.com/szeloof/status/1628528981430657026

And this twitter thread mentioned in the comments makes no mention of it: https://mobile.twitter.com/szeloof/status/154993704406717235... (Ctrl + F "Jim" or "Atomic" gets me zero hits)

Maybe I am dense, but where is Atomic Semi saying that it is being started by Sam Zeloof and Jim Keller, especially if the title is saying that (which I thought titles weren't supposed to be editorialized)?