A billionaire technology mogul has resigned from the company he founded after a series of sex scandals wiped ￡4bn off its value.

Richard White, the founder of Sydney-based WiseTech, resigned on Thursday after a string of lurid claims regarding the 70-year-old’s personal life threw the company into turmoil.

Mr White has faced claims that he had offered to invest in a beauty entrepreneur’s business in exchange for a sexual relationship, and that he paid a multimillion-dollar settlement to a woman who had accused him of inappropriate behaviour.

The scandals have caused WiseTech’s share price to fall by a fifth this week, wiping A$8bn (￡4bn) off the company’s value. Mr White, who owns more than a third of the company, has seen the value of his stake decline by billions.

This week, Mr White settled a legal battle with Linda Rogan, a beauty entrepreneur who came close to appearing in the reality TV show The Real Housewives of Sydney.

Ms Rogan had claimed Mr White bought her a A$13m Sydney mansion, but had refused to allow her to move in after his long-term girlfriend discovered the relationship, leaving her with huge bills for furnishing the house.

She claimed that the relationship began after Mr White had invited her to New York after offering to back her business, booking one hotel room for the two of them without her knowledge. The two confidentially settled the case earlier this week.

Australian media reported this week that in separate cases Mr White had paid millions of dollars in late 2020 to a former partner and gave a former employee a A$7m house after a relationship with her. A former WiseTech director also accused Mr White of “sustained intimidation and bullying” when she resigned in 2019.

Meanwhile, Zena Nasser, Mr White’s wife, with whom he had a child in July, is reported to have applied for and subsequently withdrawn an “apprehended violence order” – a restraining order for victims of or people concerned about domestic violence – in 2021.

WiseTech’s board responded to the allegations earlier this week to say it was “actively seeking further information and taking external advice”.

On Thursday, it said Mr White would stand down as chief executive immediately and take a “full-time, long-term consulting role” with the title “founder and founding CEO” on the same A$1m a year salary he was previously paid.

Mr White said: “It has been a challenging time for me personally, my family and close friends, and for the company that I have built and truly love. I want to assure all those who have supported WiseTech, as customers, colleagues, and shareholders, that I remain absolutely committed to seeing this incredible organisation continue to thrive and grow in the coming years.”