If a dependent is claimed on more than one electronically filed individual income tax return, the second return filed will receive Alert Code IND-607 informing the taxpayer of this fact:
Alert Code: IND-607 | Category: Information Message | Severity: Alert
A dependent claimed on the return was previously claimed as a dependent on another accepted return for the same tax year. Visit www.irs.gov/identity-theft-fraud-scams/identity-theft-dependents for additional information.
*** Additional Information: XXX-XX-XXXX ***
The additional information provides the last four digits of the dependent's ID number.
Even though the dependent has been claimed on more than one return, the IRS accepts the second return and starts the process of communicating with both taxpayers with the goal of determining whose return is allowed to claim the dependent.