(I'm going to regret posting this later, but...)

On Tue, Sep 25, 2018 at 10:57 PM John Curran <jcurran@arin.net> wrote:

The significant difference for ARIN is that we operate under a different legal regime, and as a matter of US law, it appears that we cannot rely only upon terms and conditions published in our website as evidence of informed agreement; i.e. within the US legal framework, we need a specific act of acceptance in order to have a binding agreement.

how is arin's problem here different from that which 'lets encrypt' is facing with their Cert things?

The “Let’s encrypt” subscriber agreement (current version 1.2, 15 Nov 2018) includes "indemnify and hold harmless” clause, and parties affirmatively agree to those terms by requesting that ISRG issue a "Let’s Encrypt” Certificate to you.

(I don’t know whether that process is particularly more or less onerous technically than the effort to download the ARIN TAL.)