The federal government is locking in a wholesale price cap on internet services providers looking to take on the NBN Co with their own high-speed rollout.

Fairfax Media and John Singleton's Macquarie Radio network are very close to finalising a $200 million talkback radio merger, less than a year after talks collapsed in bitter circumstances.

A relatively flat week on the ASX belied some dramatic moves as a busy five days of earnings results revealed some big winners and losers.

Westpac has become the latest big listed company - and the first bank - to be targeted by a shareholder campaign on business lobby groups amid Australia's long-running and vexed climate policy debate.

The Australian Securities and Investments Commission has issued reports to the boards of several investment banks on potential deficiencies in their corporate culture, as scrutiny of remuneration and potential conflicts of interest in investment banking gathers pace.