If backers of Proposition 8 are not permitted to appeal a federal judge's ruling overturning the measure, the effect of that ruling must be limited to the two same-sex couples who brought the challenge, sponsors of Proposition 8 argued Friday.

In written arguments before the U.S. 9th Circuit Court of Appeals, the sponsors, called protectmarriage.com, insisted they had legal authority to appeal last month's ruling even though the gay couples sued the state, not the proponents.