The Court of Appeal decision said Mr Biggs, a former commodities trader, was "already wealthy'' when the relationship began - his former wife estimated his assets were worth about $A20 million at that time.
During the course of their relationship, his principle business was as a fund manager for unit trusts which invested in Australian farms.
She was a secondary or eligible beneficiary in two of the trusts.
Ms Biggs said her ex-husband's net worth more than doubled during their relationship and she claimed an interest in those gains.
She said they derived from relationship property (funds taken from the couple's joint bank accounts), or represented unpaid remuneration/salary left in the business, or were attributable to her contributions.
Of the latter, that was through her "performing the role of homemaker and caregiver for the couple's child, by entertaining corporate clients, and by assisting and supporting the husband with his various business ventures''.
Mr Biggs, however, said he shared parenting duties equally; his wife did not contribute to his work with clients; his role at one of the companies was not unduly time-consuming; and he exited that role when the couple moved to Queenstown so "no question arose'' of the wife contributing by "releasing his time for business purposes''.
Ms Biggs had sought further documents and information to give weight to her claim, but following a hearing in the High Court at Invercargill, Justice Gerald Nation refused that.
The Court of Appeal hearing was largely related to that issue on grounds she needed the information to ''establish and quantify her entitlement to, among other things, a share of the husband's separate property".
The decision said 124 categories of documents were initially sought by her.
Mr Biggs claimed his former wife was "abusing discovery'' and was "trying to embarrass him in a business in which confidentiality of information is paramount''.
"He says that the discovery sought is disproportionate, for although his separate property is valuable, the wife's claim to it is both minor and weak''.
Material subject to the appeal fell in to 20 categories.
The court allowed her appeal in part, ordering discovery of some documents, including those which would identify Mr Biggs' role in the business during the relationship to gauge his extent of commitment to it.
"It will not disclose anything about the wife's contribution, but the husband has put his own commitment to the business in issue by denying that the wife released his time to attend to it, and the issue has significant implications for the wife's claim.''
It also found Justice Nation's approach to the interim payment of $200,000 was "too conservative'' and ordered Mr Biggs pay $400,000 to his ex-wife "forthwith''.
"It must be assumed that her claim to a share of separate property may be vindicated, and we accept that valuation and legal costs reasonably associated with the claim will be considerable.
"The wife has a credible claim to an interest in the husband's separate property, she is in need of funds for the litigation, and the payment will be set off against the interim distribution to the wife from the pending sale of the home, so protecting the husband's position.''
On costs, while most of Ms Biggs' requests for discovery were declined, her success was "sufficiently substantive to warrant costs in the usual way.''
