Forbes says the total value of the UK-based semiconductor company's issued shares today is $29 billion.
"I've had a hell of a good career, and he's partly to thank for that ... the least I could do was buy him lunch," Mr Jaggar told the Weekend Herald.
So yesterday, on a trip up from Christchurch to show his daughter around the university, he finally got to shake his old marker's hand.
"I knew Bob was up here, and I always wanted to meet him," he said.
"It was one of those things. When I came out of Canterbury University, I wasn't even sure if it was proper to thank him - it was almost like writing to a judge - so I never contacted him and I always regretted it, really."
His thesis, A Performance Study of the Acorn RISC Machine, got him in on the ground floor of the ARM company in Cambridge just as it was being spun out from Acorn.
His first role there was to commercialise an instruction set simulator he wrote as part of the thesis, and to facilitate rapid prototyping of ARM-based embedded systems.
Soon after, Mr Jaggar was promoted to head of architecture design, and went on to run its US engineering division based in Texas.
During his time with the company, he re-encoded the ARM 32-bit instruction set into 16 bits, called Thumb, that helped pave the way to portable, battery-powered devices.
"Thumb basically taught the processor a second language that was much more compact than the original ARM instruction set," he said. "Because of that, it really enabled the digital revolution.
Today, ARM employs nearly 3000 people and annually sells about 10 billion processors that are used in 95 per cent of the world's smartphones and 80 per cent of digital cameras.
He left ARM not long after the company went public, its share price sky-rocketing through to around 2000.
"I bailed just before the tech stock crash, and it took 12 years for the stock price to get back to where it was."
Mr Jaggar was hesitant to discuss his personal wealth, but said his early retirement should have indicated how well he'd done in the industry.
Though he had never met him, Professor Doran had long been an inspiration, especially as he'd been a computer architect with Amdahl Corporation, the Californian company that took the computer game to giants IBM in the 1970s.
"He was well known in the industry, so it was kind of a privilege to have my thesis marked by him."
Funnily enough, Professor Doran admitted he couldn't recall doing so. "David has a copy of my letter, and read what I wrote, and it was okay, yeah," he said with a chuckle. "You don't hear much from former students, so it was good to get him up."
Both hoped Mr Jaggar's story would inspire future students.
"It's a cliche, but the biggest thing is to believe in yourself and do it," Mr Jaggar said. "When I got to Cambridge, I thought those guys were going to be so far above me, but it just wasn't true; little old New Zealand turned out some really bright guys."
