Trond Mohn (left) and Frederik Mohn (right) in front of a portrait of company founder Frank Mohn - Frank Mohn AS
Their Bergen-based company, Frank Mohn AS, supplies pumps to the oil and gas industry.
"I think I pay exactly the right amount of tax. I pay it gladly," Trond Mohn, 70, who has long been Norway's largest income taxpayer, told E24.
Trond Mohn, a member of the Labour Party, said the new government's plans to limit the personal tax data made public by Norway's tax authorities was "a bad idea".
"I think tax data should remain available and open. There is a tradition in Norway of an open and transparent society," he said.
Trond Mohn earned 323.7 million kroner in 2012, while his son earned 142 million.
Next in line came hedge fund owner Espen Nordhus, with income of 104 million, followed by Seadrill chief executive Alf Christian Thorkildsen (102m), Peter Groth, chief executive of the Aspelin Ramm property group (96m).
Bestselling author Jo Nesbø was the top earner in the cultural space, with income of 39 million kroner.
Many of Norway's richest men were notable for their absence from the list of top income tax payers.