AI startups can experience meaningful valuation changes between funding rounds as model performance, proprietary data rights, compute access, strategic partnerships, and other technical or commercial milestones evolve. This guide explains when AI companies should reassess a 409A valuation, how appraisers determine common stock FMV, the three 409A safe harbor methods, and what founders should consider when selecting a valuation provider. 

As an IPO becomes a realistic near-term outcome, 409A valuations often require closer attention. This guide explains changes to the illiquid start-up safe harbor, valuation refresh cadence, grant-date scrutiny, and the relationship between 409A, ASC 718, and pre-IPO disclosure review.

An acquisition can change how existing and new stock options are treated under Section 409A. This article explains the valuation requirements for assumed or substituted options, new grants on acquirer stock, and when post-close events may require updated valuation work.