A friend sublets their apartment to 2 people, they both pay 50% of the rent and the sub-letter pays nothing, is this considered taxable income?

My friend has a lease for a 3 bedroom apartment. He is sub-letting 2 of the rooms out to people who are each paying 50% of the rent each. My friend isn't paying anything towards the overall lease amount or contributing to the rent. Is the income received from the 2 roommates considered taxable income?