Public technical disclosure of AI implementation in finance: Python-framed evidence from 253 NYSE-listed financial companies

Abstract Artificial intelligence (AI) claims in public markets increasingly raise disclosure, comparability, and investor-protection questions, yet evidence on how listed financial firms publicly describe implementation remains fragmented and difficult to compare. This study examines public technical disclosure rather than internal adoption by constructing a screened, exchange-bounded corpus for 253 NYSE-listed financial companies. The source intake contained 554 rows; six exact repeated rows were removed before screening, leaving 548 screened rows. The 505-sentence extended analysis corpus combines a 253-sentence firm-anchor layer with a 252-sentence direct-verification layer; the remaining issuer is retained in the direct-verification audit as a closed unit with no strict direct match. Firms are coded into three disclosure states: explicit Python, indirect AI, and none, and the corpus is used to map subsector profiles, channel location, and the rarity of quantified public outcome claims through an outcome claims index (OCI). The results show that 34 firms (13.4%) are classified as Explicit Python, 216 (85.4%) as Indirect AI, and 3 (1.2%) as None. Explicit Python naming is uneven across subsectors and is concentrated mainly in employment materials and technical documentation rather than in filings or investor-facing channels. The public technical surface is therefore real but thin: firms more often signal implementation orientation than disclose a detailed tool stack. Quantified public outcome claims are rarer still, with five OCI-positive firms and five OCI-positive sentences (1.98% of firms). These findings indicate that public financial-sector communication is much stronger on AI-related implementation signals than on measurable outcomes. The paper offers a reproducible disclosure map for a bounded listed firm population and a framework for distinguishing general AI language, implementation-specific technical naming, and quantified public claims in regulated capital market settings.