Md. Code, Labor and Employment § 4-307

A court does not have jurisdiction to grant injunctive relief that specifically or generally:

(1) prohibits a person from ceasing or refusing to perform work or to remain in a relation of employment, regardless of a promise to do the work or to remain in the relation;

(2) prohibits a person from becoming or remaining a member of an employer organization or labor organization, regardless of a promise described in § 4–304 of this subtitle;

(3) prohibits a person from paying or giving to, or withholding from, another person any thing of value, including money or strike or unemployment benefits or insurance;

(4) prohibits a person from helping, by lawful means, another person to bring or defend against an action in a court of any state or the United States;

(5) prohibits a person from publicizing or obtaining or communicating information about the existence of or a fact involved in a labor dispute by any method that does not involve the act or threat of a breach of the peace, fraud, or violence, including:

(i) advertising;

(ii) speaking; and

(iii) patrolling, with intimidation or coercion, a public street or other place where a person lawfully may be;

(6) prohibits a person from ceasing:

(i) to patronize another person; or

(ii) to employ another person;

(7) prohibits a person from assembling peaceably to do or to organize an act listed in items (1) through (6) of this section;

(8) prohibits a person from advising or giving another person notice of an intent to do an act listed in items (1) through (7) of this section;

(9) prohibits a person from agreeing with another person to do or not to do an act listed in items (1) through (8) of this section;

(10) prohibits a person from advising, inducing, or urging another person, without the act or threat of fraud or violence, to do an act listed in items (1) through (9) of this section, regardless of a promise described in § 4–304 of this subtitle; or

(11) on the ground that the persons are engaged in an unlawful conspiracy, prohibits a person from doing an act listed in items (1) through (10) of this section in concert with another person.