Oil In Upper And Lower Intake

I just pulled off my upper intake and noticed a decent amount of oil where there should be none at all all.

I do not have a PCV line or EGR connected. So how could oil find its way up into the intake manifold? Dosn't make much sense to me.....?

Any ideas?

How would that get into the intake manifold all the way to the throttle body though?

That's why I'm lost. With nothing connected to the intake manifold except for the vacuum leading the the fuel pressure regulator and brake booster. How would oil go backwards up into the intake when there should be a vacuum sucking the other way towards the engine...

I took everything off and applied Copper rtv to some areas I had slight leaks from. Which was where the lower intake meets the front and rear of the block. I can only think that this was a slight vacuum leak somehow causing oil to seap in from the valley in the form of smoke and settling in the intake.

That's a wild guess though.