Predatory journal / conference acceptance lure — email flatters recipient as "esteemed researcher," claims rapid acceptance of a paper never submitted (or invites keynote / chair / guest-editor role), names an unknown journal or conference, and directs to APC payment or a fake manuscript-upload page. Engine had zero academic-vertical coverage before this signal. Evidence: Thesify 2026, iConf 2026, Johns Hopkins Predatory Journals guide, Research Publishing Navigator Dec 2025, Exordo 2026

Email from a predatory publisher or fake conference flattering the recipient as an "esteemed researcher" or "distinguished scholar," claiming rapid acceptance of a paper never submitted to that venue (or inviting the recipient to serve as a keynote speaker, session chair, guest editor, or editorial board member), naming an obscure or entirely fictitious journal or conference, and directing the recipient to pay an Article Processing Charge (APC), registration fee, or submission fee — or to upload a manuscript through an Overleaf-impersonating portal. These emails often originate from free-webmail addresses (@gmail.com, @yahoo.com, @outlook.com) despite purporting to represent academic institutions. Evidence base: Thesify 2026 "Predatory Journals in 2026"; iConf 2026 conference red-flag guide; Johns Hopkins Sheridan Libraries predatory journals identification guide; PMC 2022 clinician-inbox analysis (up to 40% of unsolicited academic emails are from predatory sources); Research Publishing Navigator December 2025 "Five Red Flags"; Exordo 2026 "9 Red Flags of Predatory Conferences." This signal fills the only remaining zero-coverage academic vertical in the engine. Fires when academic flattery or role-invite language combines with fast-acceptance or fee language from a non-allowlisted publisher domain. Allowlisted legitimate publishers: springer.com, elsevier.com, wiley.com, nature.com, sciencemag.org, plos.org, acm.org, ieee.org.