Corn futures are enduring their longest losing streak since June, as the market grapples with a lack of fresh bullish catalysts following a surge of speculative buying by hedge funds.

Data from the Commodity Futures Trading Commission, spanning the past two decades, shows that as of September 1st, net long positions held by asset managers reached an all-time high. This wave of investment was initially fueled by adverse U.S. weather, which has weighed on yields in the world's top corn producer, alongside disruptions to grain flows in the Black Sea region. These factors propelled corn prices to a three-year high last week.

However, this rally has pushed the 14-day Relative Strength Index above 70, a technical level often interpreted as a signal that a pullback may be imminent. Joe Davis, director of commodity sales at an international futures firm, noted that with no new bullish drivers on the horizon, the massive long positions appear unsustainable. He stated that funds "have no room left to add to their positions," and suggested the market may have already seen a cyclical peak in corn prices for now.

On Wednesday, the most-active corn contract on the Chicago Board of Trade fell as much as 1.1%, marking its fifth consecutive session of decline.