U.S. stock futures were mostly lower early Tuesday as Wall Street returned from the long Labor Day weekend, with traders confronting a historically weak post-holiday session and rising oil prices. Polymarket’s "S&P 500 (SPX) Up or Down on September 8?" contract implied only a 28% chance of a higher open. Dow Jones futures fell 0.77%, S&P 500 futures declined 0.24% and Russell 2000 futures slipped 0.49%, while Nasdaq 100 futures rose 0.16%. The U.S.-Iran conflict continued to pressure energy markets, with Brent crude at $98.65 a barrel, up 1.70%, and West Texas Intermediate crude at $94.06, up 2.82%. Investors are watching Friday’s August Consumer Price Index report for clues about Federal Reserve interest-rate decisions, while Apple’s Wednesday product event and several companies’ earnings are also in focus. The Sept. 4 Polymarket contract resolved "Down" after recording $86,866 in trading volume, while major index-tracking ETFs ended Friday mixed.