AI drives spike in class action filings

Dive Brief:

• Securities class action filings in federal and state courts surged 30% to 121 in H1 from 93 in the second half of 2025, while ticking up 6% compared to the first half of 2025, according to a new report from Cornerstone Research, an economic and financial consulting company. 
• The 15 securities class action filings related to artificial intelligence in federal court in the first six months of 2026 show such filings are on pace to hit a number nearly double the 16 that were filed throughout the entirety of 2025, the report stated. Of those AI-related filings in H1 2026, the biggest share centered on AI development, followed by data centers, and AI hardware or infrastructure, according to the report.
• The spike in AI-related filings stems from the excitement that AI opportunities generated among issuers and investors, said Sasha Aganin, senior vice president at Cornerstone in an email. When a company is “expected to grow quickly and hits a bump on the road, its share price may decline a lot and securities class actions may follow in some cases,” he said. 

Dive Insight:

The securities class action filings during the first half of 2026 were spread across multiple companies and different sectors, including software services, semiconductors, and energy, said Aganin. 

The Second and Ninth U.S. Circuit Courts, which represent New York and California respectively, were the selected venues for a large share of the filings. The surge in federal suits was largely comprised of AI-related cases against technology companies, with filings in the sector reaching twice the 1997- 2025 average, according to the report.

The $529 billion in disclosure dollar loss during the H1 2026 period also represented a significant spike, nearly reaching the all-time high of $544 billion set in the first half of 2022. Mega filings, those that come with a DDL of at least $5 billion, accounted for 85% of the total disclosure dollar losses during H1 2026 — the third highest share of all time, behind the first halves of 2022 (89%) and 2000 (88%). 

Maximum dollar losses also increased from $1 trillion in the first half of 2025 to $1.858 trillion in the first half of 2026 — a rate that is substantially higher than the 1997–2025 semi-annual average of $667 billion. 

Despite the high numbers, there was some good news for companies. No COVID-19 related actions were filed during the first half of the year for the first time since the start of the pandemic in 2019. There were also no cybersecurity-related filings, a first since 2016, and the six total cryptocurrency-related filings during the period is on track to being the lowest number since 2019. 

The trend of AI-related filings could continue if volatility among different AI companies continues down the road, as some market observers expect, said Aganin. 

Those class actions were predominantly filed under Section 10(b) of the Securities Exchange Act of 1934, he said. They targeted both U.S. and foreign countries. 

The likelihood of a core filing, those that are not related to M&A, against U.S. exchange-listed companies in 2026 is on pace to be the highest since 2019, the report stated, while the number of core federal filings against non-U.S. issuers is on pace to reach its highest total since 2020. 

The rise in non-U.S. filings was driven by lawsuits that included “pump-and-dump” allegations, said Aganin. 

“It is not entirely clear why foreign issuers are disproportionately affected by these allegations,” Aganin said. “We know that some foreign issuers do not have particularly liquid securities traded in the U.S.”

Since the start of the second half of 2025, there have been 10 filings alleging such pump-and-dump schemes, six with tariff-related allegations, and four with private credit-related allegations involving business development companies, the report stated.