This study examines whether data-value legibility conditions the relationship between patient capital and firm productivity. We define data-value legibility as the extent to which the long-term economic relevance of a firm’ s data resources is interpretable to outside investors, and capture it through DataAssetText, a text-based signal constructed from the co-occurrence of data-asset nouns and assetization actions in MD&A disclosures. Using Chinese A-share listed firms from 2010 to 2024, we find that patient capital is positively associated with firm-level total factor productivity, and that this association is stronger when firms exhibit higher data-value legibility. The pattern is robust to disclosure-style controls, richer fixed-effects structures, alternative variable definitions, lead–lag specifications, and a supplementary instrumental-variable check. Mechanism-related evidence indicates that data-value legibility is associated with lower analyst forecast dispersion, and that its moderating role is concentrated among firms with greater ex ante valuation disagreement. Forward-looking institutional-ownership outcomes are also consistent with a commitment-sustainability interpretation. Policy-window evidence around China’s 2024 data-asset accounting policy, together with placebo, balance, and event-study checks, provides supplementary support. The findings conceptualize patient capital as a long-horizon disposition whose productivity implications depend on the surrounding information environment, and identify data-value legibility as a value-relevant property of firm communication that is distinct from disclosure intensity, generic digital orientation, and formal accounting recognition.