Main beam pocket size and stability question

I have seen a couple homes recently when doing 11th month inspections with main beams pockets that seem to be oversized, beams that are overy shimmed, and generally strike me as not stable. I am having a hard time finding documentation on building standards that outline what size the beam pocket should be, how many shims are allowed, what kind of anchoring would be needed to make sure the beam does not shift in a large pocket. Can any one give me some info? Is this size pocket okay? The fact that some of them are filled in with bricks and mortar to make up the space and some are not… it just strikes me as very wrong, but would like to point to some documentation as to why so the builder doesn’t come back with a vague answer to the homeowner saying that is is normal.

its fine, its not going anywhere. the pocket is oversized just in case it has to be moved during construction if its not square with the structure. the Shims are fine, they are there to get the beam level, as the concrete is not. with the weight of the entire house sitting on the beam it is not going anywhere. if it was a wooden beam it should not have that much open space on the sides, but the steel beam is not going to twist or bow at all over time.