A Starbucks coffee shop announces its partial reopening during the coronavirus pandemic in Baltimore, Maryland, on June 14, 2020.

Filings of securities class actions plummeted in the first half of the year, despite the coronavirus' hit on the U.S. stock market, according to a report released on Wednesday by Cornerstone Research.

According to the report, "Securities Class Action Filings — 2020 Midyear Assessment," compiled with the Stanford Law School Securities Class Action Clearinghouse, there were 182 new class action securities filings through June 30, an 18% decrease from the second half of 2019 and the lowest since the end of 2016.

The declines come amid a 25% drop in cases filed over mergers and acquisitions, but also include filings brought under Section 11 of the Securities Act of 1933, which addresses alleged misrepresentations tied to offering documents. After years of steady increases, those case filings in state courts fell to 11 from 29 in the second half of 2019, according to the report.

Jeremy Lieberman, managing partner of New York's Pomerantz, one of the top three plaintiffs firms behind this year's case filings, said most companies so far have credibly attributed their earnings drops to the COVID-19 pandemic.

"Everyone is aware COVID is out there, and if a retailer has lower sales, for example, that is relying on foot traffic for sales, and had disappointing earnings, we're not going to bring a lawsuit because that's less anticipated," he said. "A lot of the disappointing earnings are COVID-related, and credibly COVID-related, and those likely aren't worth bringing a lawsuit and likely not the result of fraud."

Phillip Kim, of The Rosen Law Firm in New York, another top filer for the year, said his firm was busy, but not with COVID-related cases. He expected that trend to continue through the year.

"I don't expect to see an increase in overall filings because of the adverse impacts of COVID-19 on companies," he wrote in an email. "The vast majority of the companies will be honest and forthright of the impact of COVID-19."

Sasha Aganin, co-author of the report and senior vice president at Cornerstone Research, said a lot depends on what happens during this season's earnings reports.

"When the earnings season in April/May came in, it was very clear that all companies across the board were hit by the virus-related slowdown that was unexpected," he said. "Now, they will need to explain it in the second and third quarter. Depending on how many disappointments companies experienced, and how the market reacts to second quarter and third quarter announcements, we may see few cases, or lots of cases."

Overall, core filings, which exclude those related to mergers and acquisitions, fell 13% from the last half of 2019. The first half of 2020 also saw a larger share of filings against foreign companies, particularly involving cryptocurrencies and cannabis, with about one-third of core federal filings against non-U.S. issuers.

"That caught my attention," Aganin said, noting that the last time foreign issuers comprised a large share of filings was in 2011, with cases brought against Chinese firms over reverse mergers.

Only 11 new cases related to COVID-19, two of which involved cruise ship companies, Aganin said.

"I was expecting more," Aganin said. "But one of the things which also happened is the market recovered very strongly."

In fact, the cases tracked the stock market's fluctuations, with filings increasing in March and April, declining in May, and then rebounding in June, according to the report. The hardest-hit industry was the financial sector, where filings jumped 50% from a year ago, the report says. Filings against technology and communication companies declined 37%, compared with the second half of 2019.

The securities report comes as Senate Majority Leader Mitch McConnell, a Republican from Kentucky, released this week his proposed COVID-19 relief bill, which includes legal protections for businesses, health care companies, educational institutions and others.

Lieberman said the report's findings of a decrease did not comport with the fear of an epidemic of lawsuits tied to the coronavirus pandemic.

"We always thought the complaint by the defense bar and Chamber of Commerce about the heightened increase of securities class actions was a bit alarmist and done for their own purposes in trying to extract some sort of tort reform or curbs on class actions," he said.