The wife of Atlassian co-founder Mike Cannon-Brookes has been accused of instructing a high-ranking executive to extract and deliver sensitive company information following the couple’s marital split.

Kevin Chiu, who served as the group financial controller and company secretary for Cannon-Brookes Services, the family’s investment firm, held his position until February of last year.

It is claimed that Chiu became entangled in the contentious fallout of the Cannon-Brookes’ separation in July 2023, ending their 13-year marriage.

A legal document filed in the Supreme Court of NSW alleges that Chiu leaked hundreds of confidential documents, including private employee HR records, to Ms. Cannon-Brookes amid the couple’s breakup.

While Chiu acknowledges he downloaded 966 files, his defense asserts that he did so at the instruction of Ms. Cannon-Brookes and as part of his routine duties.

The allegations include that around November 14, 2024, Chiu accessed and downloaded a trove of documents such as employment contracts, salary and bonus details, resumes, tax records, medical certificates, visa and police check information, and minutes from meetings.

It is alleged he shared the ‘HR Files’ with Ms Cannon-Brookes and former CBC chief financial officer Catherine Manuel between December 20, 2024 and January 10, 2025. 

The company also accuses him of leaking invoices and bank statements to Ms Manuel, as well as US tax details about sports team investments by Cannon-Brookes Entertainment Group, and details of financial dealings with Grok Investments. 

Mike Cannon-Brookes had previously gushed over his partner, Annie Cannon-Brookes , recounting how he got down on one knee to propose in 2009

Mr Chiu flatly denied the core breach allegations and insisted that providing access to Ms Cannon-Brookes was not an unauthorised disclosure. 

According to the statement of claim, Mr Chiu was employed from May 18, 2020, until  February 4 last year.

Cannon-Brookes Services alleges he breached his employment contract, which required Mr Chiu to keep information confidential, use it only for performing his duties, and not use it in ways that could harm the company, its officers, employees, or ‘the Family’.

Mr Chiu is also accused of breaching his statutory duty under the Corporations Act, which prohibits officers from improperly using company information to gain an advantage for themselves or others, or to cause detriment to the company.

On February 4 last year, during a meeting with new CFO Faris Cosic, Mr Chiu allegedly admitted to the HR Files conduct.

The company said it then issued a ‘Deliver Up Direction’ requiring him to return all devices and provide passwords and access codes, but he allegedly refused by text.

The company terminated Mr Chiu’s employment on February 4 last year and commenced proceedings against him on February 18.

Cannon-Brookes Services is seeking damages and indemnity costs for the alleged breaches.

Mr Chiu is counter-claiming for financial compensation arising from the interim court orders.

Embattled technology billionaire Mike Cannon-Brookes (pictured) and his software company Atlassian have faced a costly hit after competitors revealed new artificial intelligence tools

Annie Cannon-Brookes and Mike Cannon-Brookes arrive at The Ivy in Sydney in 2017

Atlassian’s shares plummeted 8 per cent on the NASDAQ last week

The legal action came after revelations Mr Cannon-Brookes’ worth fell almost $1billion as competitors developed new AI tools that challenge his business software products.

Atlassian’s shares plummeted eight per cent on the NASDAQ last week.

The company shares hit US$68.17 (AU$97.43), more than a third of the stock’s peak of US$242 (AU$345.88) within the last 52 weeks.

It followed tech competitors Amazon and San Francisco-based Anthropic revealing major updates to their AI products.

Mr Cannon-Brookes had previously gushed over his partner in a series of loved-up tweets when he got down on one knee to propose in 2009.

Following their engagement, he tweeted: ‘GOT ENGAGED THIS WEEKEND! The gorgeous Miss Annie said yes!’

The couple tied the knot in 2010 and amassed a huge property portfolio worth almost $300million over the years as Mr Cannon-Brookes climbed the Rich List ranks.

The couple’s 1.1-hectare Fairwater home in the Sydney harbourside suburb of Point Piper, where the late Lady Mary Fairfax lived, was the most extravagant of their purchases.

Mike Cannon-Brookes has suffered a $1billion blow with his share price collapsing

They snapped it up in 2018 despite its $100million price tag, which made it the most expensive house in Australia at the time.

‘We love the idea of raising our four young children in this historic property, filling the house and gardens with love and laughter through the years,’ Mr Cannon-Brookes told Domain at the time.

They also owned a $14.25million home in Newport, on Sydney’s northern beaches, neighbouring the $24.5million estate they purchased there in 2020.

The couple also spent $2.55million on a fisherman’s cottage out at Great Mackerel Beach on the northern beaches, accessible only by boat.