What is the ruling on marriage by exchange (shighar) in exchanging a sister for a sister?

The questioner : He says: My brother proposed to my sister, and I proposed to his sister. In the contract, they agreed on a specific amount, and the two amounts were equal in value, meaning the terms were equal. The marriage took place, so he prepared his sister, and I prepared my sister. Is there anything in this marriage called shighar?

The Shaykh : If that was on the condition of an agreement between them, it is shighar according to many scholars. If it was without such a condition, it is not shighar, and there is no harm in it.