Just a note on the recent herbicide change of Law. Special Nehmer Effective Date Rules Under the special Nehmer effective date rules, it does not matter when the VA adds a disease to the presumptive list. The rule is that the effective date is the latter of the date the VA received the initial claim for an Agent Orange-related disease (“initial claim” means the first claim filed after or pending on September 25, 1985) or the date the Agent Orange-related disease was first diagnosed. Agent Orange Back Pay and Effective Dates (SPECIAL RULES) - Hill & Ponton, P.A.