Short answer. Yes. Article 237 requires a federation or national union applying for registration to submit the names and addresses of the companies where its affiliated locals or chapters operate, together with a list of all the members in each company involved — this is a mandatory part of the registration requirements.
What the law says
The names and addresses of the companies where the locals or chapters operate and the list of all the members in each company involved.
Labor Code, Article 237 — Requirements For Federations. Read the full provision →
Federations face additional registration requirements
Article 237 adds requirements on top of what an ordinary labor organization must submit. Where the applicant is a federation or a national union, it must additionally provide proof of the affiliation of at least ten (10) locals or chapters, each of which must be a duly recognized collective bargaining agent in the establishment or industry in which it operates, supporting the registration of such applicant federation or national union. These extra requirements exist because a federation is asking to be registered on the strength of the local unions that back it.
Company names, addresses, and full membership lists
Alongside that proof of affiliation, the article requires the specific disclosure your question asks about: the names and addresses of the companies where the locals or chapters operate and the list of all the members in each company involved. This is stated as a submission requirement, not an optional attachment — a federation seeking registration must identify both the employers where its affiliated locals operate and the individual members within each of those companies.
Why the disclosure ties back to the ten-local threshold
These two requirements work together. Proof of affiliation with at least ten locals establishes the federation's claimed base, and the company names, addresses, and membership lists give the registering authority a concrete way to verify that base — which companies the locals actually operate in, and who their members actually are. Without both pieces, the affiliation requirement alone would be difficult to confirm.
What this means for a federation preparing to apply
A federation cannot treat this disclosure as optional or something to supply later if asked. Because Article 237 lists it as an additional requirement alongside the ten-local affiliation proof, an application missing the company names, addresses, or member lists is missing part of what the registration process demands from a federation or national union specifically, as distinct from what an ordinary single labor organization has to submit. Preparing this information in advance, company by company and member by member, is generally more efficient than trying to assemble it after the registering authority has already flagged the application as incomplete.