Many of the negative stories have been aired in the Australian, whose national chief correspondent, Hedley Thomas, has become Palmer's chief bete noire.
Among other things, Thomas has reported allegations that he is a "tyrannical bully" who shouts and swears at his executives and employees.
This week, Palmer, fed up with leaks to the media, ordered all his staff to sign a four-page confidentiality agreement. One of them leaked the contract to Thomas.
Now the MP for the Sunshine Coast seat of Fairfax has gone on the offensive.
Before his speech on Monday, he threatened to use parliamentary privilege to expose alleged corruption by the Liberal National Party (LNP) government of Campbell Newman.
The Queensland state premier, in turn, branded the PUP a "sick political joke" and all about "the ego of one man ... and his business interests".
In the event, Palmer - who was once the LNP's biggest donor, but fell out with the party after failing to win approval for a new coal project - kept his powder dry, at least as far as Newman was concerned.
Instead, he championed the cause of women, the poor and Aboriginal Australians, accusing Parliament of being "deaf to the everyday struggles" of ordinary voters.
"On this small speck in the universe, planet Earth, we must do what we can to help each other," declared Palmer, who beat the LNP candidate by only 26 votes in Fairfax.
"We live in a nation where ... the infant mortality rate of our indigenous people is twice that of the Australian community, where the life expectancy of many of our poorer and downtrodden citizens is less than it should be ... where our elderly and veterans are forgotten ... where despair of the homeless and unemployed robs the nation of the productivity of our citizens."
Palmer called for greater female representation in Parliament and the Cabinet, citing Mao's assertion that "women hold up half the sky".
And, in an apparent nod to King's "I have a dream" speech, the man who may, possibly, be a billionaire - pundits are divided on the size of his fortune - asserted that "the content of our character is more important than how much money we have".
A fair chunk of his own money has been spent on lawsuits against political foes and media organisations.
But his claim never to have lost a case does not reflect reality. Last week the owner of the defunct soccer club Gold Coast United withdrew a A$10 million defamation action against a Football Federation Australia arbitrator who found he had acted "dishonourably" towards a player, and against a newspaper and journalist who reported that finding.
Meanwhile, a French media executive, Didier Guerin, is reportedly consulting his own lawyers after he was allegedly called a "f*** wit" by Palmer for complaining that his Black Angus steak - which he had asked to be served "blue" - was overcooked. The MP allegedly told him: "Don't speak to my chefs like that. I own this resort and I want you to f*** off."
