Pretty clear from the records pages now that the Owl Sector is a civilian organisation from the City that liases with the Guardians in the tower and supports them. They appear to be the foerunners to SIVA, some of the communique's talk about they were designed to speed up the building of colony's and used for enhancing colonists. It's clear that this is how the SIVA threat returns to the world, and is the lead in for Rise of Iron. There was a line in there about Saladin storming in and demanding to know what they were..