Trafficking Reduction and Criminal Enforcement (TRACE) Act - Directs the Attorney General to require each firearm manufactured in the United States to be marked with a serial number that is located inside the barrel of the firearm or that is visible only in infrared light, in addition to the serial number marking otherwise required.
Amends the Commerce, Justice, Science and Related Agencies Appropriations Act, 2010 to repeal provisions prohibiting the use of appropriated funds: (1) to implement a national instant criminal background check system that does not require the destruction of identifying information within 24 hours after the system determines and advises a federal firearms licensee that a person's possession or receipt of a firearm would not violate federal or state law, or (2) to promulgate or implement any rule requiring a physical inventory of a licensed firearms dealer.