As per Shrimad Devibhagwat and Padma puran, Lord Bhairav blesses this Rudraksha.
Its ruling planet is Ketu, which is a shadow planet like Rahu. 9 Mukhi is beneficial to sublimate the ill effects of Ketu. Ketu inflicts the diseases of lung, fever, eye-pain, bowel pain, skin disease, body pain etc. Wearing 9 mukhi rudraksha keeps a check on the malefic effects of planet ketu and prevents the wearer from any body and health related problems. It is ideal to be worn on left hand or right arm.
9 Mukhi also helps in removing the Kaal Sarp Yoga effect. When worn in combination with 8 Mukhi and 11 Mukhi Rudraksha.