A few years ago, a number of U.S. states tried to ban "rbGH-free" claims on dairy. Monsanto, which owned rbGH at the time, helped found a group called AFACT, which supported the bans. AFACT was unsuccessful in most states, but it looked like they might win in Ohio, where the fight went to the courts.
Recently, however, the Ohio court came to its decision. First, they ruled that milk in Ohio can still bear an "rbGH-free" label as long as it also bears the disclaimer stating that, "[t]he FDA has determined that no significant difference has been shown between milk derived from rbST-supplemented and non-rbST-supplemented cows."
But there's more important news out of Ohio -- the court also challenged the FDA's finding that there is "no measurable compositional difference" between milk from rbGH-treated cows and milk from untreated cows. This FDA finding has been the major roadblock to rbGH regulation, and the court struck it down.
According to La Vida Locavore:
"The court ... [cited] three reasons why the milk differs: 1. Increased levels of the hormone IGF-1, 2. A period of milk with lower nutritional quality during each lactation, and 3. Increased somatic cell counts (i.e. more pus in the milk)."