I think it's Cali
and Oregon that don't allow FA products. I did a little more research and it seems like there's no accepted standardized test for Fulvic concentrations in products. There are 3 main tests, each producing very different results (one test could show a product containing 8%, one could show up as .08% depending on the testing methods) because the methods are different in how they extract and weigh FA chemicals.
Great article here.
I'm guessing it's hard to trust the FA concentrations on labels, or there is not enough consistency, so Cali/Oregon said no (the only 2 states in the country), but it's weird because they allow humic acid products (and those test results can vary substantially as well).