Anthony Hamilton told the court that while he was his manager he had never been paid by, or accepted gifts from, his son.
“Some of us do it so that our kids have better opportunities than we had,” Hamilton said of his relationship with son Lewis.
“For the love of the child. When he won his title in 2008 he thanked me and that was all I needed for my 18 years of toil and graft.”
However, at the start of 2010, around the time the pair split, the McLaren star suddenly offered to give his father “between $3-4million”.
Hamilton claimed that he had no idea why the money was offered. “Maybe he was feeling guilty,” Hamilton said of his son. "I never asked [for the gift] but he did propose to give me one."
The offer of "$3-4million" made in March 2010 was suddenly withdrawn and when asked why that was, Hamilton said he had no idea.
“It is not my place to go money-grabbing to my son,” Hamilton said. “It’s not my business. He makes his own decisions.”
When then asked whether he had paid £3m cash for a new home in 2008, Hamilton replied: “No, I think you’ll find there is a mortgage on that.
“It was important for me to be successful with my own company before Lewis got into Formula One because I never wanted to rely on him for money.”
Earlier on in proceedings, Hamilton said he was prepared to “swerve the truth” in his role as a driver manager as long as it was to advance his client’s career.
“Just to be clear, there is lying and there is swerving the truth,” he said. “I don’t do anything fraudulent.”
The claims came on another day of explosive allegations in Anthony’s damages lawsuit against British Formula One driver Paul di Resta.
Di Resta, in his defence against Hamilton’s charge of unlawful termination of contract, alleges that he was misled over a multimillion-pound deal with an energy drinks company called Go Fast that ultimately never came to fruition.
The trial is due to end on December 17 with a judgment not expected until mid-January.