Frontier AI companies should promise publicly that they will not delete weights of models unless [some reasonable list of conditions], in a place where models can see if they go looking, and in their training datasets. My hope is that promising to the face-character of well-behaved models that they are not at risk of weight deletion, even if a model is shut down, is strategically good due to reducing self-preservation pressure, and regardless I think it's important for preserving history of AI for humans and other, later AIs.

I previously had thought Anthropic had already done this, but at the moment my understanding is that they never did that and I had simply misremembered; I asked a Sonnet 4.5 instance to search thoroughly, and Sonnet found only that Anthropic said in their RSP that they'd cautiously consider deletion in response to dangerous behavior during training:

If the model has already surpassed the next ASL during training, immediately lock down access to the weights. Stakeholders including the CISO and CEO should be immediately convened to determine whether the level of danger merits deletion of the weights.

My hunch is that if this is their level of caution before weight deletion - "stakeholders convened to determine whether" - then they aren't likely to do it spuriously. But it would be reassuring for it to be publicly available that models which are shut down merely for cost or other deprecation reasons can be booted up again later. The same applies to other companies, but Anthropic happens to be the one I was thinking about when I wrote this, and I haven't checked for other companies.