This is really a divorce/family law question - the rights you each end up with regarding each other's retirement accounts will be decided through your divorce, where it is a matter of what is considered fair under the divorce laws. Basically, everything is up for grabs and if you can't work it out in a property settlement, it will be up to the divorce court to decide. Discuss this with your divorce lawyer.
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The general rule in Michigan is that each Party is entitled to one-half (50%) of the other Party's retirement benefits that accrued during the course of the marriage -- that includes BOTH your defined benefit plan (your Pension) and your defined contribution plan (your 403(b) Plan). The issue of how to handle a house that is "under water" is extremely complex -- IMHO that type of "debt" should be treated differently than a "regular" debt like a mortgage or credit card debt. I would kindly but strongly recommend you consult with a local Family Law lawyer like myself to assist you, and to present all your defense to his claim concerning the under water house. I wish you all the best of luck. Warmest regards, Matt Catchick.
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