Here is the hyperlink to the LIUNA Election officer web page . This has always been the policy but it has never been stated by the Election Officer. The International provides its membership list to the AFL-CIO, insurance companies (Ullico), Credit card companies etc  Locals can always choose to be liberal and require candidates to sign a statement that the list will not be used for commercial  gain and/or only for this election. Candidates nominated for international office get a list of the members that will vote for them. The same rules apply to locals with combined elections because International election rules apply.

http://www.liuna-eo.org/candidate%20rights.htm

Right to Inspect Local Membership List:  Nominated candidates have the right to inspect a list of the names and last known addresses of all Union members eligible to participate in the Convention Delegate election.  The candidate is entitled to exercise this right at least once within the 30 days prior to the election.  The right of inspection does not include the right to copy the list, although a candidate can compare the list with a personal list of members.  Locals may choose to permit copying of the list, but if they do so all candidates must be permitted to obtain a copy at the same time and on the same terms.