"And it goes to show that angel investing isn't a millionaires' club.
The total value of the sale was not disclosed, but it is understood to have been a multi-million dollar deal with Microsoft acquiring 100 per cent of the company, which will become part of the Microsoft Azure cloud platform.
GreenButton was founded by chief executive Scott Houston, the former chief information officer for Weta Digital. Some of its largest customers include US-based companies Pixar, NASA and Boeing.
Marcel van den Assum, a director and the lead investor in GreenButton, said the Tauranga investors had given the software start-up great support at a critical phase.
"We got healthy interest from Tauranga, which was really pleasing,'' he said.
"It's part of the seed process where you get investments that at that time are relatively small, but crucial to get the company to the next level.''
Mr van den Assum, who is also currently chairman of the Angel Association of New Zealand, said over 20 individual angels had contributed, including investors from Angel HQ in Wellington and Ice Angels in Auckland, as did early stage venture funds Movac, Sparkbox and Evander.
He also acknowledged the support the company has had from the government, including the New Zealand Venture Investment Fund, Callaghan Innovation and New Zealand Trade and Enterprise.
Mr Houston said that Microsoft's purchase was great news for the GreenButton team, their investors and other New Zealand companies.
GreenButton
Founder - former Weta Digital chief information officer Scott Houston
Business offering - solutions to harness cloud-based computing power for intensive digital workloads
Acquirer - Microsoft Corp. for its Azure cloud platform
Investors included - Tauranga Enterprise Angels members