The Pennsylvania Supreme Court ruled that mail ballots with missing or incorrect dates will not be counted in the upcoming November election, reversing a lower court decision. Republicans hailed the ruling as a victory for election integrity, while Democrats and voting rights groups warned it could disenfranchise eligible voters. The court's decision, which could affect thousands of ballots in the critical swing state, was based on procedural grounds, noting that the initial lawsuit did not include all 67 county boards of elections. This ruling continues a long history of litigation over mail voting requirements in Pennsylvania, with further legal challenges still pending. The decision may have significant implications in a state that could be pivotal in the presidential race and control of the Senate.