Maryland Family Law Section 10-308
§ 10-308.
  (a)   A tribunal of this State issuing a support order consistent with the law of this State has continuing, exclusive jurisdiction over a child support order:
    (1)   as long as this State remains the residence of the obligor, the individual obligee, or the child for whose benefit the support order is issued; or
    (2)   until all of the parties who are individuals have filed written consents with the tribunal of this State for a tribunal of another state to modify the order and assume continuing, exclusive jurisdiction.
  (b)   A tribunal of this State issuing a child support order consistent with the law of this State may not exercise its continuing jurisdiction to modify the order if the order has been modified by a tribunal of another state pursuant to this subtitle or a law substantially similar to this subtitle.
  (c)   If a child support order of this State is modified by a tribunal of another state pursuant to this subtitle or a law substantially similar to this subtitle, a tribunal of this State loses its continuing, exclusive jurisdiction with regard to prospective enforcement of the order issued in this State, and may only:
    (1)   enforce the order that was modified as to amounts accruing before the modification;
    (2)   enforce nonmodifiable aspects of that order; and
    (3)   provide other appropriate relief for violations of that order which occurred before the effective date of the modification.
  (d)   A tribunal of this State shall recognize the continuing, exclusive jurisdiction of a tribunal of another state which has issued a child support order pursuant to this subtitle or a law substantially similar to this subtitle.
  (e)   A temporary support order issued ex parte or pending resolution of a jurisdictional conflict does not create continuing, exclusive jurisdiction in the issuing tribunal.
  (f)   A tribunal of this State issuing a support order consistent with the law of this State has continuing, exclusive jurisdiction over a spousal support order throughout the existence of the support obligation. A tribunal of this State may not modify a spousal support order issued by a tribunal of another state having continuing, exclusive jurisdiction over that order under the law of that state.