Its shares listed at the $1.15 offer price, but declined more than 4% to trade at $1.10.
More than 60% of the IPO shares have been allocated to New Zealand and Australian institutional investors, including Milford Asset Management, Salt Funds Management, Harbour Asset Management, AMP Capital, Zeus Management and Sam and Gareth Morgan.
The $65 million IPO, at $1.15 per share, implies a market capitalisation of $118 million.
Wynyard managing director Craig Richardson said Wynyard was now majority-owned by New Zealand investors, reversing a recent trend of high growth New Zealand tech companies being sold to overseas investors.
''The company raised capital to continue its global expansion, develop new sales channels and invest in its risk management, intelligence, investigations and digital forensics software products,'' Mr Richardson said in a statement Craigs Investment Partners broker Chris Timms said there had been a lot of selling.
More than 1.45 million trades had been made by 2pm, possibly by short-term traders. Wynyard employs more than 120 staff in New Zealand, Australia, United States, Canada, United Kingdom and the United Arab Emirates.
Wynyard was spun out of Jade Software and is the latest listing for the NZX, which has already added state-controlled power company Mighty River Power, and search engine developer SLI Systems.
Dairy processor Synlait Milk will join the bourse next week, BusinessDesk reported.
The funds raised will go towards the $23.6 million price tag on the intellectual property rights of Wynyard's intelligence products, which are owned by Jade. About $10 million will repay intercompany debts and a $2 million loan Jade wrote to fund Wynyard's investment. Another $3.6 million is expected to cover the listing costs, leaving $25.8 million to fund growth.
The company expects to post a net loss of $10.1 million this calendar year on sales of $21.5 million, and a loss of $10.4 million on sales of $27 million in 2014.
Mr Richardson said the company had a ''favourable'' first half, acquiring new contracts in New Zealand and expanding its customer base in the UK and United Arab Emirates. It also boosted capability in the US.
''Recent world events have only strengthened Wynyard's competitive advantage and global value proposition,'' Mr Richardson said, in reference to the heightened public sensitivities around the reach of national spy agencies into metadata.
Wynyard software is in use by the London Metropolitan Police and the New Zealand and Australian police forces, global banks and corporations, and is making inroads into the huge US market, where its products have impressed the Department of Homeland Security.
• Wynyard's data scientists and software engineers build intelligence-led software to protect companies and countries from threat, crime and corruption and has more than 400 clients globally, including financial services, government and critical national infrastructure organisations, the company said.
