I have been looking into the rules that govern a 401(k) plan maintained by a Guam based corporation. I am finding that most of the same tax and ERISA rules apply, whether a plan is maintained by a US based domestic corporation or a Guam based corporation. For a Guam based corporation, certain documents, most notably the 1099-Rs, would need to be filed with the Guam tax department. However, it appears that the IRS Form 5500 needs to be filed with the US DoL. I was wondering whether there were any other special rules or caveats that apply. Thanks in advance for any insights.