BE stands for "Belgium." Some of the well-known international companies that trade on the Belgium stock exchange, and which could be the source of your foreign dividends on Form 1099-DIV, include AB InBev (owner of Budweiser, Miller, and many other beer brands), and ING Group (international bank and insurer).
A complete list of other foreign countries, and their international codes (as used and recognized by the Internal Revenue Service) can be found at the following IRS.gov chart:
https://www.irs.gov/tax-professionals/e-file-providers-partners/foreign-country-code-listing-for-mod...
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