While Howard is well known in business circles, it was the trial of Sharon Collins that made him more of a household name when the divorced mother-of-two was accused and found guilty of conspiracy to murder him and his two sons, Robert and Niall in 2006.
Collins was also convicted of soliciting an Egyptian poker dealer Essam Eid to murder the three men.
During the trial, the prosecution maintained she was motivated by money and was attempting to inherit PJ Howard's €60m fortune.
She had lived with Mr Howard in his plush home on the outskirts of Ennis.
The 48-year-old, from Kildysart Road in Ennis Co Clare, was sentenced to six years after being found guilty in 2008.
She was accused of using the alias 'lyingeyes98' in her bid to hire a hitman over the internet.
Eid was extradited to the US in May to face criminal charges in California.
Since her release after four years in prison, her solicitor, Patrick Moylan, has revealed she is in talks over a book deal.
Accounts filed for Howard's company Waymill Ltd show assets went from €10,183,000 for the year ending 2010 to €10,261,897 for 2011. But the company also recorded debts of €6,034,783, meaning net assets were listed at €4,227,115.
Howard's wealth has been estimated at being in the €60m region, and he is also the director of two other companies -- Lapovo and Diownes & Howard.
Life on the outside for Collins is much different than that of the sun and champagne lifestyle prior to her conviction in September 2008.
The doors to PJ's Spanish penthouse are firmly closed.
He cut all ties with her in September 2009, when he made his last visit to her at the Dochas Women's prison.
Collins's conviction on three counts of conspiracy to kill her millionaire lover and his two sons put a halt to any travel plans to many countries including the USA and Canada.