The subsidiary, Rural Community Insurance Services (RCIS), is based in Anoka, where it employs 400 people.

Wells Fargo has launched an auction for the business that could fetch more than $1 billion, people familiar with the matter said. When contacted by Reuters, Wells Fargo said it is reviewing strategic options for the RCIS subsidiary that may include a sale, excluding the Wells Fargo Insurance Crop Agency, its brokerage arm.

“Wells Fargo regularly evaluates the strengths and strategic fit for each of its businesses. As our model continues to evolve, we are more focused on increasing cross-sell and growing the distribution side of the insurance business,” a Wells Fargo spokeswoman said in a statement.

Bidders for RCIS could include reinsurers seeking exposure to the primary insurance market such as Bermuda-based PartnerRe Ltd. or Axis Capital Holdings Ltd., the sources said. Muenchener Rueckversicherungs Gesellschaft in Muenchen AG or Allianz SE are also potential buyers, the sources said. Axis and PartnerRe declined to comment, MunichRe and Allianz did not immediately respond to a request for comment.

Crop insurance helps farmers protect themselves from financial ruin when drought, disease, freezing temperatures, hail, or wind destroy their crops. About 90 percent of planted farmland is covered by insurance every year.

A combination of low interest rates and extreme weather such as flooding and drought have combined to make the business unattractive to many financial institutions and companies of late. OneBeacon Insurance Group Ltd. and Monsanto Co. are among those to have sold their crop insurance arms in recent months.

Banks have been under increased pressure from U.S. regulators to strengthen their balance sheets and take on less risk, and this has also weighed on their ability to participate in the insurance business. Goldman Sachs Group Inc., for example, sold its Global Atlantic Financial Group Ltd. insurance unit in 2013.

Wells Fargo now plans to be active in crop insurance through its insurance brokerage arm.

RCIS collects more than $2 billion in premiums annually from farmers. It has more than 4,000 licensed agents who can insure 137 types of crops.