Philips (PHG.AS) and Shell (SHEL.L) were recently targeted by Cl0p, the hacking group said in a statement on its website.
Philips said it had been targeted by Cl0p while Shell said it was aware of a recent "possible incident", confirming an earlier report by Dutch media outlet BNR.
"We are working with our security teams and relevant experts to investigate the situation," a Shell spokesperson said.
"Philips has identified and contained an attempted cybersecurity compromise of a specific enterprise server related to internal data," Philips said in a statement, adding that the incident does not impact customer environments.
Cl0p, a ransomware operation known for developing and exploiting vulnerabilities in various file transfer programs, posted the names of a group of major companies on its website on August 12, saying it had stolen large amounts of data.
The group claims it stole roughly 89 gigabytes of data from Shell, including engineering drawings, photos of facilities, scans of facility testing reports, and project plans. The group claims it stole roughly 13.5 gigabytes of data from Philips, including PDF drawings, diagrams, and blueprints.
The group has not shared any samples of the data it stole, and did not respond to requests for comments sent to two email addresses it advertises as being active.
Neither Shell nor Philips confirmed whether data had been stolen.
