The latest data point for PFE's short interest, as of 2026-02-27, stands at 2.52%, reflecting a modest pullback from the prior period's peak of 2.58% on 2026-02-13, amid ongoing fluctuations in investor sentiment. Over the period from 2025-09-30 to 2026-02-27, short interest has exhibited an overall upward trend, rising from 2.01% to 2.52%—a net increase of approximately 25%—with notable acceleration in late 2025 and early 2026, peaking at 2.58% before the recent dip. Key inflection points include a steady climb through November 2025 to 2.45%, a brief decline to 2.29% by December 2025, and renewed growth into February 2026, suggesting building bearish pressure despite intermittent volatility; no data is available for the subsequent 2026-03-13 period. The area chart visualization underscores this gradual accumulation, highlighting short interest as a potential indicator of downside risks for PFE shares in the near term.