Neb. Rev. Stat. § 77-2734.11

(1) A corporate taxpayer is taxable in another state if that state has jurisdiction to subject the taxpayer to a net income tax regardless of whether, in fact, the state does or does not do so. (2) The failure to provide upon request of the Tax Commissioner a copy of the return filed and proof of payment of a net income tax imposed by another state creates a rebuttable presumption that the taxpayer is not subject to tax in the other state.