Apparently they aren't CARB compliant
Here's some info I got from this link:
http://forum.ih8mud.com/camping-gear-recovery/200120-scepter-fuel-cans-carb-states.html
"With regards to the CARB compliance, the portable fuel container has to meet these requirements
1. Single opening
2. Self venting
3. Auto shut off spout
4. Auto close spout
5. Low permeation wall
Scepter MFC meets all these CARB requirements except for #2 and maybe #5. For #5, if the walls of the MFC are not low permeation, then Scepter will have to change the plastic formulation of the MFCs. For #2, the design of the cans follow the traditional jerry can, with a built-in air vent to prevent splashing and increase flow rate."