Mark A. Rosenbaum v. Pamela Shaw, 459 P.3d 467

Mark Rosenbaum (father) and Pamela Shaw (mother) have a daughter born in 2002; Mark paid court-ordered child support (including half of health-insurance cost) and last modified support in 2009.
Mark retired and began receiving Social Security retirement benefits in 2012; the daughter became eligible for a derivative children’s insurance benefit (CIB), and Pamela received monthly CIB payments from 2012–2016.
Neither parent notified the Alaska Department of Revenue, Child Support Services Division (CSSD) about the CIB; CSSD learned of the CIB in 2016 and credited Mark with a $47,432 overpayment (because CIB can offset support).
Mark sued seeking (1) judgment forcing Pamela to repay or be credited for the $47,432 overpayment and (2) reimbursement/credit for half of the health‑insurance premiums (~$7,574) he paid after adding the child to his plan in 2013.
The superior court denied both remedies, ordered CSSD to remove the prior overpayment credit and to apply only month‑by‑month offsets for future CIB payments, and adjusted future support; the Supreme Court of Alaska affirmed.

Issue	Plaintiff's Argument (Rosenbaum)	Defendant's Argument (Shaw)	Held
1. Can Mark recover (by reimbursement or future credit) a $47,432 overpayment caused by duplicative CIB and child‑support payments?	Pacana controls; overpayments are recoverable and should offset future obligations.	Overpayments made while CIB satisfies the obligation are gratuitous; policy and precedent disfavor retroactive recovery.	Denied — voluntary duplicative overpayments treated as gratuity; remove past credit and allow only contemporaneous monthly CIB offsets.
2. Is Mark entitled to reimbursement/credit for half of the child’s health‑insurance premiums he paid since 2013?	He paid the premiums and should be repaid for his out‑of‑pocket costs.	Retroactive modification of child support (Alaska R. Civ. P. 90.3(h)(2)) bars retroactive credit; notice/ procedural rules govern insurance offsets.	Denied — retroactive credit/reimbursement barred; court prospectively adjusted support to reflect insurer cost allocation.

Pacana v. State of Alaska, Dep’t of Revenue, Child Support Enf’t Div., 941 P.2d 1263 (Alaska 1997) (adopted rule that CIB payments may be credited against child‑support arrears).
In re Marriage of Stephenson & Papineau, 358 P.3d 86 (Kan. 2015) (following Andler: duplicative monthly payments are gratuitous and not recoverable).
Andler v. Andler, 538 P.2d 649 (Kan. 1975) (holding duplicative monthly child‑support payments satisfied by CIB are gratuitous).
Epperson v. Epperson, 835 P.2d 451 (Alaska 1992) (past voluntary excess contributions do not justify reducing future support).
Wicker v. Hallman, 245 So. 3d 627 (Ala. Ct. App. 2017) (voluntary overpayments not entitled to credit against future support).
Rathbone v. Corse, 124 A.3d 476 (Vt. 2015) (permitting reimbursement for payments during SSDI pendency to encourage continued payments).
In re Marriage of Allen, 386 P.3d 1287 (Ariz. Ct. App. 2016) (trial court discretion to credit duplicative payments under state guidelines).