It is legal (with some restrictions) in California, but in the other 49 states it is generally regarded as illegal.

I myself feel that lane splitting (when done correctly) is much safer, when in heavy traffic. When I lived in California I owned a Honda Goldwing (1979 GL1000), and split the lane whenever possible.

Tom

Those who would give up essential liberty to purchase a little temporary safety deserve neither liberty nor safety. Benjamin Franklin, US author, diplomat, inventor, physicist, politician, & printer (1706 - 1790)