(1) A claimant is an interested party to proceedings that adjudicate claimant's eligibility and qualification for unemployment insurance benefits.

(2) The department is an interested party to proceedings that adjudicate any and all issues related to benefit claims and employer tax liability.

(3) Except as provided by 39-51-605, MCA, and ARM 24.11.208, an employer who paid wages to the claimant is an interested party to proceedings that adjudicate the claimant's separation from employment with that employer. Proceedings that adjudicate the claimant's separation from employment during the base period of a claim determine whether any portion of benefits paid to a claimant are chargeable to the base period employer's account pursuant to 39-51-1125, 39-51-1212, or 39-51-1214, MCA. An employer is not an interested party to proceedings that adjudicate nonseparation issues related to a claim.

(4) An employer is an interested party to proceedings that adjudicate the employer's own tax liability, contribution rate, application for refund, subject wages and other tax contribution-related issues.

(5) Any person may provide the department with information relevant to an investigation or determination of a benefit claim or an employer's tax liability. Unless a person is an interested party to a proceeding, the department shall not notify the person of the determination and the person does not have standing to contest the determination.

(6) Only an interested party to an unemployment insurance proceeding has standing to request a redetermination, hearing, or appeal to the Unemployment Insurance Appeals Board.

(7) The department shall provide written notice of a determination, redetermination, hearing, and appeal only to the identified interested parties to a particular proceeding as defined by this rule.