Maryland Code, Election Law § 13-301

(b)(1) An out-of-state political committee shall register with the State Board on a form that the State Board prescribes within 48 hours after directly or indirectly making transfers in a cumulative amount of $6,000 or more in an election cycle to one or more campaign finance entities organized under Subtitle 2, Part II of this title.

(2) The registration form the State Board prescribes shall require an out-of-state political committee to designate the election year in which the committee is participating.

(1) disclose all expenditures made in the State by the out-of-state political committee:

(2) describe how to access the campaign finance reports filed by the out-of-state political committee in the state where the committee is registered and files the reports; and

(3) be filed in the manner and subject to the sanctions provided in Parts VI and VII of this subtitle.