An income tax expense contains both current and deferred tax. The total tax expense includes income tax expense and the current year's tax obligation.

 Company "A"  has an income tax report which shows income tax expense as  $12.3 million and current year's tax obligation as $7.9 million . So the difference in the amount needs to be calculated which will give us the deferred tax.

Calculate deferred tax of Company A as shown below:

 Deferred Tax = (Income tax expense - Current year's tax obligation)

Deferred Tax = ($12.3 - $ 7.9) =$4.4 million.

Hence, the deferred tax liability of company "A" is $4.4 million