Assistance in collection of tax claims: cross border enforcement and conservatory measures permitted subject to domestic law limits. Assistance requires competent authorities to accept requests to collect or take conservatory measures for a tax claim (including interest, penalties and collection costs); the requested Party shall collect or apply conservatory measures under its domestic law as if the claim were its own, including interim asset freezing where authorized. Accepted claims receive no special time limits or priority in the requested State; jurisdictional challenges on existence, validity or amount remain with the requesting State; assistance is subject to domestic law, public policy exceptions, prior exhaustion of reasonable measures by the requesting State and proportionality of administrative burden, and requests may be suspended or withdrawn if the claim ceases to qualify.