It can depend on various factors, such as the laws in the jurisdiction where the couple lives and any prenuptial or postnuptial agreements they may have signed.
In some cases, the engagement ring may be considered a gift from the giver to the recipient. Thus, it may be considered the recipient’s property to keep even after a divorce. In other cases, the ring may be considered a conditional gift, meaning that the recipient must return the call if the condition (in this case, marriage) is not fulfilled.
If the engagement ring is a family heirloom or was given as a gift to the recipient specifically, it may be easier to determine ownership. However, if the ring was purchased jointly or is of significant value, it may require legal intervention to decide who will keep it.