The new national regulations require is that you have a current veterinarian inspection every time you cross a state line. Many states have had this requirement already, but this makes it mandatory in all states.
In case you don't live on a farm or ranch then you wouldn't be privy to a mini-war that has been going on between the USDA and the producer associations. The previous National Animal Identification System (NAIS), which was the original voluntary system proposed by USDA to deal with disease outbreaks and traceability, caught a lot of heat from the industry. There were a lot of concerns over complexity, confidentiality, liability, cost and privacy, it was not supported and this is the beginning of the "new approach". USDA reconsidered its approach and decided that rather than attempting to identify every animal, every premise, and every movement to achieve traceability within 48 hours of a disease outbreak, it would develop a more limited and simpler system. The new system does not require the registration of premises housing livestock or the specific reporting of individual movements of horses.
Under the new rules, horses moved interstate must be accompanied by an ICVI or other document acceptable to the states involved. The person or entity responsible for moving the horse interstate must ensure it has an ICVI or other document.
The APHIS representative, state representative or accredited veterinarian issuing the ICVI or other document must forward a copy to the state health official in the state of origin within seven days of issuing the document. The state representative in the state of origin must forward a copy to the state representative in the state of destination within seven days of receiving it. In the event of a disease outbreak, these documents will be used to trace horses that are or have been at the site of the outbreak and horses that have come into contact with them.
While not specifically referenced, movement documents could also include an event passport.