The Mallinckrodt Pharmaceuticals sign was unveiled at the company's offices in St. Louis on July 1, 2013.

Opioid maker Mallinckrodt's stock jumped by more than 15% on Friday after hitting an all-time low the day before and reaching tentative settlements in two opioid lawsuits set to go to trial next month.

"Mallinckrodt is pleased we were able to reach a settlement in principle with the counties that made sense for all parties," General Counsel Mark Casey said in a statement Friday announcing the agreements "in principle" with the Ohio counties of Cuyahoga and Summit. "Resolving the Track 1 cases gives us the necessary time to continue to work towards a global resolution of the opioid lawsuits."

If the deal is finalized, Mallinckrodt will pay $24 million and donate another $6 million in generic products.

The company's stock bottomed out Thursday, plunging 39% to $1.59 a share amid reports that it might file for bankruptcy. On Friday, the shares surged 17.6% to close at $1.87.

Mallinckrodt CEO Mark Trudeau told investors at a conference Thursday that the "rumors and speculation are unfortunate." The company's shares have lost 95% of their value over the past year and are even further from their 2015 peak of $132.51 a share.

Bloomberg on Wednesday reported that Mallinckrodt, which agreed Wednesday to pay $15.4 million to settle a drug bribery probe into a company it acquired in 2014, hired law firm Latham & Watkins and turnaround firm AlixPartners, citing unnamed sources. The drugmaker is facing mounting litigation tied to the U.S. opioid crisis.