Morgan Stanley (MS -1.38%) has agreed to pay a $5 million fine to the commonwealth of Massachusetts to settle allegations of impropriety relating to the Facebook (META -10.56%) IPO earlier this year, a court filing reveals. The investment bank, which was the lead underwriter of the IPO, had been accused of violating securities laws in its conduct of the Facebook issue, and of acting in a "dishonest and unethical" manner.

In paying the fine, Morgan Stanley neither admitted nor denied the charges.

Massachusetts' punitive action is not its first in relation to the Facebook IPO. In October, syndicate member Citigroup (C -1.09%) paid the commonwealth a $2 million fine over similar accusations.