Who owns the house in a finalized divorce when it was not asked for by spouse?

If property is jointly owned and not divided, it remains jointly owned.  There are 2 ways to divide property in divorce, by agreement or court order.  If an asset is jointly owned, but not addressed in distribution, each party maintains their state law rights. The same is true of all property.  There is no obligation to address property at all in a divorce and that is why the Notice to Defend and Claim Rights attached as the first page of the divorce complaint notes that a party may lose rights if not exercised.  Assume for the sake of discussion that all assets were titled in one person's name, the parties were married for 30 years with all those assets being acquired during the marriage, and a divorce complaint is filed.  Unless the other party seeks a division of the marital assets, they will lose any rights they had under the divorce code. The same is true with jointly owned property.  Unless it is divided, the state law rights apply and each party maintains whatever interest they had in that property before the decree.  If the house is not jointly owned, but only by you, you maintain sole ownership.  If the opposite is true, he maintains sole ownership.