Tom Henderson, the founder and former chief executive of the disaster-relief charity ShelterBox, is facing a retrial over allegations he fraudulently awarded contracts worth £1.5m to his son.
After more than 30 hours of deliberation, a jury at the Old Bailey has been unable to decide whether Tom Henderson, 65, his son John, 36, and associate Darren Gervis, 43, had committed fraud.
Both the Hendersons and Gervis had faced charges of conspiracy to commit fraud between January 2007 and December 2012.
Henderson set up the charity in 2000 and under his leadership it grew into an organisation with an income of almost £20m a year by 2010.
But Henderson treated the charity, based in Helston, Cornwall, as "his own personal fiefdom", putting its worldwide reputation at risk, the court heard.
He allegedly ensured his son's companies were favoured to supply the charity with stoves, tents and multi-tools between 2007 and 2012 in deals worth hundreds of thousands of pounds.
When trustees of the charity began to ask questions, the Hendersons allegedly brought in Gervis to set up sham companies to hide the fraud, the court was told.
But Tom Henderson told the court he stayed at arm’s length from any business deals between the charity and his son.
John Henderson said he believed they were only arrested because the new management needed to bolster their employment tribunal case against his father after they "screwed up" by sacking him, jurors heard.
After deliberating for a week, the jury of seven men and four women told the judge they were hopelessly deadlocked.
Judge Gerald Gordon said: "They are unable to reach any verdict against any defendant and they have been in that position since Monday."
He told the jury: "It would be not only pointless, but also quite wrong to ask you to continue."
The three defendants now face a two-week wait as the Crown Prosecution Service decides whether they should be retried.
Alison Wallace, chief executive of ShelterBox, said in a statement: "It is very disappointing that these matters have yet to be resolved. It would not be proper for ShelterBox to comment further until we know how the Crown Prosecution Service wishes to proceed."
Gervis, Tom Henderson and John Henderson all deny conspiracy to commit fraud.