It does not necessarily need to be something that companies actively do, it's also that the process is set up that way. For example, I know I was not actively s

It does not necessarily need to be something that companies actively do, it's also that the process is set up that way. For example, I know I was not actively seeking other opportunities until I got my green card. IIRC, even transferring to a slightly different role within the same company could affect how quickly the process progressed (I think part of the paperwork would need to be re-filed).