In fairness, Ultramarines didn't get to be in Angels of Death. But, then again, neither did Black Templars, and I refuse to follow the apologist line that Black Templars were part of Gathering Storm I, so that's where that is.

But anyway, lollerskates...
Gathering Storm I: Coteaz makes everything ObSec.
II: Aeldari Boogaloo: Eldar get no ObSec.
III: Guilliman In Time: All Ultramarines are ObSec.