How Does Fine Filtration Affect Additive Depletion?

Fine filtration filters contaminants down to less than 5 microns. So with such fine filtration, does that also mean that you risk additive depletion? According to Noria Corporation, yes and no.

According to Noria, a good additive package should be fully blended and dissolved in the base oil. Therefore, fine filtration should not be able to strip out any additives. 

However, many additives are polar in nature and have the ability to cling to particles. Many do so to fulfill their protective roles within lubricants. By doing their job, these additives will deplete over time by filtration/separation or simply fall to the bottom of the oil reservoir. Once they attach to the particle and the particle is removed by filtration, the filter does remove the additives, but it was just doing its job. The additives would have been depleted anyway.

(Read more about fine filtration, oil life and additive depletion in the full Noria article, "Can Fine Filtration Extend Oil Life?"...)