Although formal, e.g., generative, approaches to linguistic inquiry are primarily concerned with the analysis of structural patterns, ethical concerns for the elicitation and documentation of empirical data that motivate these analyses persist. In this article, we explicate the challenges to be met and responsibilities that formal linguists must take in data collection, documentation, and analysis to ensure high ethical standards. We direct our attention especially toward research on heritage, minoritized and endangered languages, which have enriched the theoretical landscape in recent decades. Finally, we show that, when proper ethical concerns are recognized and accounted for in formal research, this collective body of research in its current form is also fully capable of respecting the integrity of individual speakers and their communities.