Equifax Inc (EFX) shares fell 7.02% on September 4, driven primarily by regulatory risks and a potential structural shift in mortgage reporting requirements. The Federal Housing Finance Agency (FHFA) is evaluating a move from the traditional tri-merge credit reporting model to a bi-merge framework for Fannie Mae and Freddie Mac mortgages. This proposed change threatens to eliminate a significant portion of Equifax's recurring revenue stream, as lenders would no longer be mandated to pull data from all three major bureaus. Compounding these regulatory headwinds, the FHFA has publicly criticized credit reporting agencies for excessive fees and restrictive pricing practices. The agency signaled that it is considering structural shifts that could lead to mandated fee reductions or expanded alternative credit scoring frameworks, such as VantageScore 4.0, which poses a direct threat to Equifax's traditional scoring structures and pricing power in the mortgage ecosystem. Market sentiment was further dampened by insider selling activity, specifically a Form 144 filing from Chief Financial Officer John W. Gamble Jr., who submitted notice to sell approximately 4,500 shares valued at over $845,000. While Equifax reported annual revenue of $6.07 billion and net profit of $660.30 million, the immediate threat of volume cuts in domestic mortgage reporting outweighs its broader growth initiatives in the short term, leading to sustained market caution. Technically, Equifax shows a neutral MACD signal but an RSI suggesting neutral conditions with a Williams %R indicating a sell condition. Analysts maintain Buy ratings with an average price target of $210.69, though the stock underperformed the Industrial & Commercial Services sector amid concerns that heightened government oversight could weaken its medium-term earnings trajectory.