National tax data shows that 179 children aged five or under filed returns for rental income.

Where property is acquired in the name of a minor, particularly an infant, the source of funds becomes the issue. Since the age group has no income, acquisition money is in principle treated as a gift.

Tax law provides deductions exempting gifts up to a set amount. Where funds exceed the deduction, a gift tax return and payment must follow.

In practice, drawing up loan agreements between family members to treat transfers as lending rather than gifts has been flagged as a problem. In such cases, whether interest is paid and repayments are made becomes the subject of verification.

Once rental income arises, it is recorded as the child's own income. Analysts note this produces a structure in which gaps in asset formation widen at the point of intergenerational transfer.

The tax authorities conduct regular reviews of funding sources where minors acquire property. Publication of the figures offers a check on how the system operates in practice.

The legality of individual cases cannot be judged from the data alone, and circumstances differ according to how each acquisition was made.