Every time I have seen a corporate officer file an FBAR, or say a US CDN person with a corporation, they report all of the business accounts. I have never seen it done differently.
For example, I was on the board for a not for profit as the Treasurer and had to report that on my FBAR. I just had signature authority.
Think about it: The US uses this form to go after people hiding offshore accounts. The corporation would be an easy place to avoid the reporting. Everything that a US person can move money around from they want to know about it.
"Please note that any person or entity subject to the jurisdiction of the United States (includes individuals, corporations, partnerships, trusts, and estates) having a financial interest in, or signature or other authority over, bank accounts, securities, or other financial accounts having a value exceeding $10,000 in a foreign country shall report such a relationship. Although there are some limited exceptions, filing requirements also apply to taxpayers that have direct or indirect control over a foreign or domestic entity with foreign financial accounts, even if the taxpayer does not have foreign account(s). For example, a corporate-owned foreign account would require filings by the corporation(if it's not a US corporation then this doesn't apply) and by the individual corporate officers with signature authority. Failure to disclose the required information to the U.S. Department of the Treasury may result in substantial civil and/or criminal penalties."
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