A new report indicates many companies are using a combination of unrelated press releases and SEC filings to hide bad news.

According to a study by the University of Notre Dame, many companies will often issue an unrelated press release at the same time they issue an SEC Form 8-K containing bad news. The goal appears to be distracting investors.

“Consistent with our prediction, we find that managers disclosing negative news via SEC Form 8-K are more likely to issue a concurrent press release about an unrelated event when compared to managers disclosing positive or neutral news,” said Jessica Watkins, assistant professor of accountancy in Notre Dame’s Mendoza College of Business. “We also find that managers more commonly issue concurrent unrelated press releases when they have stronger incentives to divert investors’ attention away from 8-Ks disclosing negative news, including when they have an upcoming stock sale.”

According to the study, 40% of 50,000 non-earnings 8-Ks contained bad news. Meanwhile, 33% were accompanied by an unrelated press release. The study also showed “that managers are more likely to file 8-Ks with negative news during periods with low investor attention, typically on Fridays or after-market hours.”

“We find it surprising this behavior is so effective,” Watkins said. “Investors should not assume press releases cover all events happening at a company at a given time.”

Investors wanting the full picture would do well to carefully scrutinize press releases and 8-K filings, especially when news is released during ‘periods of low investor attention.’