The institutional NPPES pool is ~98% not_on_list org NPIs, which land on a
soft/green result in the public NPI tool ('you're basically fine') -- so they
click and leave with no buy trigger. The providers who get a RED 'revalidation
PAST DUE, CMS may deactivate' result (a real $599 reason to act) are the CMS
revalidation-overdue NPIs.
This joins the CMS Revalidation Due Date List to NPPES endpoint emails and
applies the warmup deliverability gates in the correct order, critically
re-filtering Google by REAL MX *after* SMTP verification populates mx_provider
(a one-off manual run on 2026-06-26 filtered on the pre-verify empty mx_provider
column and leaked 214 sends to Gmail, earning a low-reputation bounce).
