Final answer:
While the case specifics are crucial, Victoria's federal trademark registration under the Lanham Act generally provides strong protection despite Don's earlier state registrations. Federal law and the principle of federal preemption often favor federal trademark registrants, and Victoria's federal protection is a significant factor.
Step-by-step explanation:
When Victoria registered a trademark under the Lanham Act but was later challenged by Don, who had previously registered the mark in several states, the outcome would depend on the specific facts of the case and the application of federal trademark law. Generally, federal registration provides strong protection across all states, but there are circumstances where prior state registration could be significant.
Here, however, federal law tends to favor the federally registered trademark unless Don can prove specific legal exceptions. It is important to conduct careful searches prior to registering a trademark to avoid potential conflicts. In many cases, federal registration is considered superior to state registration due to the principle of federal preemption. Therefore, without further details on how Don's previous state registrations might affect Victoria's federal registration, it's difficult to predict the exact outcome, but Victoria's federal protection under the Lanham Act is a powerful defense.