Wisconsin Insurance Commissioner Sean Dilweg is imposing a $750,000 fine on a health insurer.

Dilweg is imposing the fine on Humana Insurance Company, a unit of Humana Inc., Louisville, Ky.

Wisconsin regulators found a number of concerns, including evidence that Humana may have paid commissions it should not have paid to agents selling Medicare Advantage and Medicare Part D plans.

The examination that led to the fine covered a period extending from 2005 to 2007.

Humana has agreed to pay the fine to resolve the investigation but has denied the allegations in the Wisconsin exam report and any violation of the law.

“Humana’s primary concern is always our members, and after review of our records and the cases in question, it appears that there was no significant impact to members,” the company says in a statement.

Humana says it is addressing or already has addressed Wisconsin regulators’ concerns.

The agent commission payment problems involved only 62 of the 5,588 Wisconsin agents doing business with Humana, and those agents accounted for only 80 of Humana’s 73,577 Wisconsin Medicare plan enrollments, the company says.

“While fewer than 0.1% percent of plans sold are at issue, even one such error is too many, and we are committed to addressing these issues quickly and thoroughly,” Humana says.