What is needed is a court ruling or an action of Congress which states that Obama is ineligible. That has never happened. Congress has ignored the issue and the courts have consistently ruled in Obama’s favor on natural born citizenship and Article II, Section 1 eligibility.
For example:
Rhodes v MacDonald, U.S. District Court Judge Clay D. Land: “A spurious claim questioning the president’s constitutional legitimacy may be protected by the First Amendment, but a Court’s placement of its imprimatur upon a claim that is so lacking in factual support that it is frivolous would undoubtedly disserve the public interest.”—U.S. District Court for the Middle District of Georgia, September 16, 2009.