IBM shares are on track for their worst trading day in nearly four decades after the company released preliminary second-quarter results that missed analyst expectations.

The technology giant reported adjusted earnings per share of $2.93, a figure that fell short of market consensus, triggering a sharp sell-off in premarket trading.

The market reaction was immediate and severe, with IBM shares falling more than 17% in premarket trading.

The surprise release of the preliminary data caught investors off guard, as the company had not previously signaled such a significant deviation from forecasts.

The market reaction was immediate and severe, with IBM shares falling more than 17% in premarket trading.

The steep decline reflects investor frustration with the company's ability to meet its financial targets amid shifting demand dynamics.

The sell-off underscores the sensitivity of large-cap technology stocks to earnings misses, particularly when guidance is not provided to offset the disappointment.