Wikipedia's Rocket Lab links to Spaceflight Insider's Rocket Lab: The Electron, the Rutherford, and why Peter Beck Started it in the First Place which links to The Otago Daily Time's 2009 arrticle Fisher and Paykel fuelled flames in novice rocket-maker which says:
He went on to work on the design of superyachts and spent five years working for Crown-owned Industrial Research Ltd, before setting up his own company.
"I reached a point where it was time to do something, so I formed Rocket Labs, quit the day job and managed to secure investment to be able to start the [space] programme."
He sold half to investor Mark Rocket.
He agreed it would be fair to describe him as "the brains" and Mr Rocket "the money" behind the venture.
And shows a photo of (apparently) the two with the caption:
Rocket Labs technical director Peter Beck (left) and business development director Mark Rocket at the unveiling of a mock-up of the Atea 1 suborbital space rocket in August. Photo by NZPA.
Question: Is half of Rocket Lab still owned by Mark Rocket? Or was there some subsequent dilution as Rocket Lab grew and became a wholly owned New Zealand subsidiary of Rocket Lab the public American aerospace manufacturer? Assuming the answer is "No", are both of their ownerships still roughly comparable?