The government's path to a Google Tax began innocuously enough when then Treasurer Joe Hockey in May 2105 announced a Multinational Anti-Avoidance Law that was framed in a way that would catch virtually nobody.
It was aimed at foreign companies that used contrived arrangements to avoid having a taxable presence in Australia, and initially it seemed likely to catch less than 20 companies.
Operations like Google, Microsoft, Airbnb and Uber, where sales are all booked offshore, were touted as companies that could face scrutiny.
But tax laws are uncertain beasts, often subject to the law of unintended consequences.
By the time the legislation came into effect last January its scope had widened, with Tax Commissioner Chris Jordan announcing that "about 1000 companies" would need to consider if the new law applied ot them, "and around 80 will need to look at restructuring".
By November the Tax Office had written to 175 companies that they could have a liability, and was already auditing 19 companies for MAAL compliance.
Is this mission creep? Or a realisation that the problem was bigger than first thought?
The Diverted Profits Tax will generate more complaints than MAAL because it potentially affects a much larger slice of Australian business. It is the onshore equivalent of MAAL, targeting companies in Australia that avoid tax by transferring profits, assets and risks offshore through artificial related-party transactions.
Add the DPT and the MAAL together and you get the Australian equivalent of the UK's so-called Google Tax.
In comparing them, it depends how you tell the story. Both the UK law and the Australian DPT draft are triggered when profits are moved to a country that charges tax at 80 per cent below the resident tax rate.
So the DPT is triggered in the UK when profits are moved to a country that pays 16 per cent tax, while in Australia the trigger is a country with a 24 per cent tax rate. That reads like Australia's DPT is tougher.
Alternatively you could say that the UK trigger point is 4 per cent less than the UK tax rate of 20 per cent, while Australia offers a 6 per cent discount on its 30 per cent rate, which suggests the UK law is tougher.
For the last year Commissioner Jordan has been calling out multinationals for stalling ATO audits, refusing to provide information or dragging out the process. "Enough is enough," he told the Senate Estimates committee in March.
The DPT draft states explicitly one of the goals is "to discourage multinationals from delaying the resolution of transfer pricing disputes".
The DPT draft gives the Tax Office a powerful hammer to do this. But it will be controversial.