Frontier lab spending. Internal safety budgets at Anthropic, Google DeepMind, OpenAI and others are not disclosed by area and likely exceed philanthropy in interpretability, evaluations and alignment.
Venture capital. Investment in safety-adjacent startups sits behind paid databases.
Government money. UK AI Security Institute, NSF, EU programmes and similar are not yet included.
Private donors. Individual and family-office giving is not public. Manifund search returns 50 projects per query, so some older Manifund projects may be missing.
Note: a thin area is thin in public philanthropy terms, not necessarily underfunded nor thin overall.