It's pretty much an IMTU decision.
The way I run the IISS Imperial Grand Survey [that's the official title of the Survey office] is this:
- Earlier in their history, when the Imperium was actively expanding, the Scouts were definitely on the lookout for colonizable worlds and resources for exploitation. But now in the Golden Age the Imperium has matured and is not looking to push the borders outward. To be completely honest, the Imperium has enough trouble staying communication with the worlds she already has. Oh, there might be some expansion into District 268, or acquiring some new worlds in Gateway or Crusis Margin, but it's widely felt that the Imperium has reached its 'natural borders'. [If only somebody could convince the Zhodani of that...]
This doe not mean that the IGS has 'nothing to do'. Societies are living, breathing things. They change and evolve. Those changes need to kept updated for a host of reasons... political, economic, sociological, etc. And not every resource has been accounted for. While the Second Survey was a vast improvement over the First, it takes **years** to fully chart every body in the average solar system and the great surveys simply didn't take that much time with the work. The Scouts were spread very thin trying to get the Second Survey done with a generation's worth of work! This is the boring drudgery of survey life... Jumping into Oort Clouds to see if the rocks are still in place... but these detailed surveys often come up with resources or scientific discoveries that were overlooked by 10,000 years of spaceflight and 3 empires!
And it is the IISS' job to be **completely** impartial in regards to their surveys, no matter who it benefits or who it inconveniences. The megacorps and nobles have had undue influence on Scout policy in the past. This has led to failed colonies [with the subsequent loss of lives], exploitation of native sophonts [ditto], undue profiteering that has led to tradewars, and a host of other symptoms of malice and decay in the service.
During his reign Emperor Strephon has appointed Senior Scout Leaders and Sector Scout Leaders with the specific mission of cleaning up the service. Some have been issued Limited Imperial Warrants with that mission in mind.
Again, all this is IMTU. This is how **I** run it, a struggle against decadence and laziness, but you're gonna run it your way and that's just fine.