The attack, the Rockville, Maryland-based company says, likely happened in mid-November, when a ransomware group accessed data on certain systems, deployed malware to prevent access to files, and then threatened to leak the exfiltrated files.

Despite that, Supernus Pharmaceuticals says it did not experience a significant impact on its business, as its operations were not seriously disrupted by the incident.

“The Company continues to operate without interruption and does not currently anticipate paying any ransom amounts to any criminal ransomware group,” the company says.