You can be too big to fail, but you can never be too big to be sued.

The US Department of Justice has filed an antitrust lawsuit against Google, accusing the internet giant of maintaining an illegal monopoly over search and search advertising.

At the heart of the suit is Google’s multi-billion dollar deal with Apple to be the default search engine on iPhones.

ACCC Chair Rod Simms says the US courts could find Google’s dealings with Apple to be anticompetitive.

“It’s one of the biggest antitrust cases we’ve seen for the last 10 or 20 years, it’s incredibly significant,” Mr Simms tells Brooke Corte.

“This is a very large company with considerable market power basically entering into agreements to entrench that market power,

“It’s a hugely important case.”

Click play to hear the full interview: