Hi, thanks for submitting your question today. Under the Employee Retiement Income Security Act (ERISA) a plan administrator would be required to provide a material plan changes in writing. The method of furnishing this writing, according to the regulations, is supposed to be a "reasonably calculated to ensure actual receipt of the material by plan participants, beneficiaries
and other specified individuals". The regulation further states "Material distributed through the mail may be sent by first, second, or third-class mail. However, distribution by second or third-class mail is acceptable only if return and forwarding postage is guaranteed and address correction is requested. Any material sent by second or third-class mail which is returned with an address correction shall be sent again by first-class mail or personally delivered to the participant at his or her work site."
So there is some requirement that mailed brochures be forwarded, but, to my knowledge, unless you leave a forwarding address with the post office, then you would not get the brochure. Return Receipt and delivery confirmation is not necessary, but they would have an obligation to find you if they received a non-deliverable return from the post office. You can view the particular regulations here
If it was the case that they relieved a non-deliverable return from the post office, and you were prejudiced because of it, then you'd have a possible fiduciary violation claim against the plan. And you may want to report the same to the Dept of Labor - Employee Benefits Division here
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