Californians who donated money to the campaign to pass Proposition 8 will not have their identities kept secret, a US federal court has ruled.
Prop 8 took away the rights of gay and lesbian couples to get married in California.
It was approved by 52% of voters in a state ballot in November and brought to an end almost six months of legal same-sex weddings.
The names and addresses of most donors to the Prop 8 campaign are already in the public domain but the court was asked to conceal the identities of 1,600 late donors.
The state is due to release their details on Monday.
Prop 8 supporters claimed that donors had been harassed and suffered death threats. Some had their businesses boycotted.
However, the court’s ruling has been hailed by the organisation that enforces campaign disclosure laws.
“This clearly is a victory for the people of California and disclosure,” said Roman Porter, executive director of the California Fair Political Practices Commission.
“The commission will continue to vigorously defend any suit brought against disclosure of campaign statements.”
There are legal challenges to Prop 8′s validity before the California Supreme Court.
In May 2008, the court ruled against a previous Proposition approved in 2000 that defined marriage in the state as between a man and a woman.
It ruled that laws that treat people differently based on their sexual orientation violate the equal protection clause of the California Constitution and that same-sex couples have the same fundamental right to marry as other Californians.
Proposition 8 challenged this ruling by explicitly denying gay people the right to marry.
18,000 same-sex couples got married before Prop 8 passed.
On November 19 2008 the California Supreme Court granted review in the legal challenges to Proposition 8 and established an expedited briefing schedule.
Oral argument could be held as early as March.