8>What is withholding tax?
8>When a dividend (or royalties or interest) is paid internationally, the country from which the payment is made usually taxes the payment as it leaves, by 'withholding' a proportion of it, usually between 10% and 30%. If there is a double tax treaty between the two countries concerned, it is often possible to reduce the tax, or to reclaim some or all of the money. Some receiving countries allow the withheld tax to be set off against domestic tax liabilities.

Видимо, зависит от договора регистратора с разработчиком. Например, share-it действует как reseller — формально он покупает у вас и продает конечным клиентам => здесь речь не идет о дивидендах, роялти и процентах. У Plimus, похоже, то же самое:

c) RIGHT TO PURCHASE AND RESELL. Vendor hereby grants to Plimus, and Plimus hereby accepts, the non-exclusive, non-transferable right to market, distribute and sell the Product to End Users using the Plimus service.

Насчет других регистраторов — надо смотреть, есть ли упоминание dividend/royalty/interest в договорах.

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