I agree with your take as well craigakess - this is another potential scenario. You can have a final agreement with conditions precedent to the parties' obligations.
Rather than that scenario, I was assuming NP meant a term sheet/LOI that is non-binding on its face save for a few provisions (e.g., confidentiality, governing law, no-shop, etc.). This was the case with the Prostagene acquisition (term sheet was 7/18, with definitive agreements in 11/18).
Doesn't really matter too much one way or another, as long as the deal closes and the Paulson-style raises are a thing of the past!