Most SaaS products rank on Google but are completely invisible to ChatGPT, Perplexity, and Google Gemini — the channels where an estimated 40 percent of B2B software discovery now happens. This guide diagnoses exactly why AI engines ignore most SaaS tools, runs a 15-minute AI visibility audit, and delivers four specific fixes — from content restructuring and schema markup to review platform strategy and citation source building — that move your SaaS from invisible to recommended.