And so it is with all other Freezones at least in Dubai.Expect the UAE to enact tax anti avoidance legislation at some point maybe even adopt GAAR. This behaviour you describe will fall under GAAR as an abusive practice to reduce your tax base by using an excessive salary. I wouldn't do this in a place like UAE until they publish there CT compliance obligations and penalties.
Maybe the below is true but who knows. But knowing UAE you will have to wait and see if any FZ tax breaks given to investors are honored.
https://www.natlawreview.com/article/update-uae-introduces-corporate-tax
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Companies incorporated in UAE’s free zones or financial free zones will also be subject to the federal corporate tax. However, it appears that such companies will continue to enjoy applicable tax breaks and incentives in the manner and for the duration set out under the legal framework of the relevant free zone authority.
For instance, Dubai International Finance Centre (DIFC) law and the Abu Dhabi Global Market (ADGM) law provide that a DIFC- or ADGM-incorporated company is subject to a zero tax rate for a period of 50 years from the time the law in question enters into effect. Accordingly, DIFC- and ADGM-incorporated companies could expect to remain subject to zero tax rate until 2071 and 2063, respectively.
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Like @rowena says - managing your personal investment is not a business activity.If you read well what you says is true only for "other income earned by individuals that does not arise from a business or other form of commercial activity licensed or otherwise permitted to be undertaken in the UAE.""
But if you are actively managing your investments from UAE online/trading as most people do and think they are safe by doing so, professional tools and a frequency above some yearly threshold, coudln't this in theory be seen as a professional commercial activity ?...
Guys come on - stop doing as UAE would be starting from 1st June of 2023 another Germany.