Public Software Companies Down 50% in Six Months as Market Rerates Sector

The leading public B2B software companies have lost more than half their market value over the past six months, with the SaaStr.ai Index of top 25 public software companies hitting negative 50.5% as of April 10, 2026. For the first time in history, public software companies now trade at a price-to-earnings discount to the S&P 500, according to data from the index. The forward P/E multiple for application software has collapsed from 84x in 2021 to 22.7x today. Jason Lemkin, founder of SaaStr, described the decline as a structural re-rating rather than a temporary correction. The market is effectively saying that software is no longer a premium business, Lemkin wrote. The implied long-term growth rate for a representative public SaaS company has dropped from 4.7% just three months ago to 1.1% today, with approximately 85-95% of enterprise value affected through terminal value calculations. Two primary forces are driving the decline. First, budget displacement, as CIOs redirect spending toward AI infrastructure, with approximately 75% of new hyperscaler infrastructure spending in 2026 targeting AI. Second, substitution fear that AI agents may structurally reduce the value of traditional seat-based software. The decline spans category leaders including Atlassian down over 50% year-to-date, HubSpot down over 50% in the past year, Salesforce down over 30% in Q1 2026, ServiceNow down over 30% in Q1, and Workday down over 30% in Q1 2026 alone. Companies that have held value share common characteristics as infrastructure plays where AI creates rather than substitutes demand. Palantir has gained 135% in 2025 with revenue growth at 70% year-over-year, while Cloudflare has positioned itself as infrastructure for AI with projected 2026 revenue of $2.79 billion at 28-29% growth.