Dear Floyd Mayweather, you’re why the SEC exists

Australia has a system called "imputation credits" or "franking credits".

Say a company BigCo makes an operating profit of $100. They decide to pay that out as a divident to shareholder Mary. Australia's company tax rate is 30%, so BigCo sends $30 to the tax department, and the remaining $70 to Mary.

Say Mary's personal tax rate is 50%. On the face of it, Mary would pay 50% of the $70 (ie. $35) to the tax department, leaving $35 in her own pocket. However, this would mean that the original $100 profit had been taxed at 65% ($30 + $35)! This is seen to be inequitable, and a disincentive to owning shares.

So instead what happens is this, Mary gets a "franking credit" of $30 along with the $70 dividend. The franking credit is just a book-keeping entry to record the amount of tax that BigCo paid on its original $100 profit.

At tax time, Mary's accountant proceeds as follows. (1) Add the franking credid ($30) to the divident amount ($70), thus reverse-engineering BigCo's original profit ($100). (2) Apply Mary's personal tax rate (50%) to that whole profit, getting $50. (3) Ensure the tax department gets that $50, regardless of who and where it comes from!

In this case, BigCo has already paid $30 of the $50 total tax obligation on the original $100 profit, so Mary is only up for the remaining $20. By that means, BigCo's original profit of $100 is eventually taxed, in total, at Mary's personal tax rate of 50% - not at the double-taxed rate of 65%.

This might just seem like a whole lotta shakin' goin' on - but wait, there's more!

Say the dividend was paid to another company (SmallCo) instead of to Mary. SmallCo's tax rate is also 30%, so when you apply the franking credit, you'll find that SmallCo pays no tax on the $70 dividend.

Now say it was paid to a self-managed superannuation fund (SMSF) in so-called "transition to retirement" phase. These are only taxed at 17%. 17% of $100 is $17, so the total tax expected by the tax department, on the original $100 profit, has been overpaid by $13 ($30 - $17), and the tax department will refund that $13 to the SMSF! The SMSF gets the $70 dividend, and not only pays no tax on that, but also, gets a $13 refund cheque.

Then we get to the apogee of this process, the quintessence of financial wizardry, a situation so warming to the heart as to impose some risk of dangerous palpitations. Say the SMSF has gone into "pension mode". In that mode, it pays no tax. Thus, when the fund receives the $70 dividend, it also receives a full refund of the $30 tax originally paid by BigCo!

As I understand it, BigCo can actually choose to pay the full tax, part of the tax, or no tax, on its origial $100 profit. The dividend is correspondingly said to be "fully franked", "partly franked", or "unfranked". A dividend recipient ("X") might get a mixture of franked and unfranked dividends from various sources. "X" would add all franking credits to a notional "franking account", then use that account at tax time to offset their normal tax obligations.

[edit: typos]

Also, you are begging the question compared to your remark about how ICOs and stocks are similar in your top level post.