[dharmab]

They're different. Filtering is between stopped cars, splitting is in moving traffic.

[snozolli]

This is completely arbitrary Internet lore. Unless you have local laws that define the terms, they don't actually mean anything. Also, if you're "filtering", then you will, inevitably, find yourself "lane splitting" when the light turns green before you reach the front.

[dharmab]

I do in fact have a local law defining the terms: https://ridetolive.utah.gov/lane-filtering/

And I rarely find myself splitting when the light changes; I simply dip back into the lane when the light changes before traffic starts moving.