Mark Shuttleworth's R250 million exit charge is still at stake as court battles wage on.

The South African government has been granted leave to appeal a Supreme Court of Appeal ruling that forced it to refund billionaire tech entrepreneur Mark Shuttleworth R250 million.

Shuttleworth founded Thawte and sold it to VeriSign for $575 million in 1999, before founding venture fund HBD and setting up the Shuttleworth Foundation, which funds change in society. In April 2002, he flew into space, as a cosmonaut member of the crew of the Russian Soyuz mission TM34, to the International Space Station, and subsequently developed Ubuntu.

Shuttleworth paid over the exit charge when he applied for permission to move R2.5 billion out of South Africa in 2009 when he emigrated to the Isle of Man. He subsequently sought to recoup the exit charge, arguing the government's position around foreign exchange controls constrained small businesses.

The legal wrangle over the exit charge, introduced in 2003, moved from the North Gauteng High Court to the Supreme Court of Appeal before making its way to the Constitutional Court.

The Constitutional Court, the highest court in SA, yesterday granted the South African Reserve Bank and finance minister Nhlanhla Nene the right to appeal the Supreme Court's ruling that the R250 million must be paid back to Shuttleworth.

The Supreme Court had found the exit charge was unlawful, ordering it be paid back, but reversed the high court ruling that government must rework the legislation. The Constitutional Court also denied Shuttleworth leave to appeal the constitutionality of the law.

At the time of the Supreme Court ruling, Shuttleworth said the amount, plus interest, would be placed in a trust, to underwrite Constitutional Court cases on behalf of those whose circumstances deny them the ability to be heard in courts when the counterparty is the state.

In yesterday's majority judgment, the Constitutional Court said the regulations that prohibit exporting capital are constitutionally valid.

This, it said, is because "the broad discretionary powers granted to the minister ensure a speedy and flexible approach to our exchange control system and are reasonably necessary to stem the outflow of capital, protect the local currency and safeguard the domestic economy". The court did not make an order as to costs.

Shuttleworth has not commented on the decision.