I didn’t find “one source,” you need to google a bit. It seems like it was implemented as part of the corporate tax reform II and the new regulation entered into force in 2009
You can find some information here for example:
“A withholding tax of 35% is levied on
dividends, interest from publicly offered bonds, debentures and other instruments of indebtedness issued by Swiss residents; and on bank interest. However, with respect to dividend income,
if the individual recipient holds at least 10% of the share capital of the distributing company, only 60% of the dividend is taxable for federal income tax purposes. Switzerland does not levy withholding tax on royalties.”
https://www2.deloitte.com/content/d...uments/Tax/dttl-tax-switzerlandguide-2015.pdf
But it seems like that has been changed again this year (and the 80% discount that I found was apparently only given on cantonal taxes):
“Private “qualifying shareholders” (i.e., those holding at least 10% of the share capital) previously benefited from a privileged dividend tax treatment at both cantonal and federal levels.
As of 1 January 2020, such dividend income will now be taxed at a rate of 70% (previously taxed at a rate of 50% or 60%) at the federal level, regardless of whether the shares are held as a private or as a business asset. On a cantonal level, the taxation of qualifying dividends ranges between the rates of 50% and 70%.”
https://home.kpmg/us/en/home/insigh...rm-implications-for-individual-taxpayers.html
So it’s not/no longer as good as I hoped. Sorry for getting your hopes up.
Here is a specific calculation for salary vs. dividends in German:
https://www.vermoegenszentrum.ch/ra...rung-fur-unternehmer-lohn-oder-dividende.html
It shows that it is now better to pay out profits as a salary after all.
At least it seems like it also applies to foreign companies. Note that there are no
CFC rules in Switzerland. So you could probably still make use of the deductions if you own a company with economic substance in another country.