You can also put in $150,000 each as a non concessional...

You can also put in $150,000 each as a non concessional contribution or $450,000 each and trigger the bring forward rule.
On top of this you can also put up to $1.315 million each on the sale of a business if you meet certain small business rules.
So an individual has the ability to put into super:

1. Non concessional contribution: $450,000
2. Small business exemptions:$1,315,000
3. Concessional contribution (over 59) $35,000

So total that can be contributed all at once = $1,800,000.

So we can have a couple potentially contribute $3.6m to super at once. Of this the grand amount of $70,000 would be in the taxable portion and $3.53m in the tax free portion.

Tax leakage indeed!!!!!!!!!