More than half of the 233 SuperAmerica convenience stores that Marathon Oil Corp. sold off in October have changed hands again.

Realty Income Corp., a real estate investment trust near San Diego, has acquired 135 SuperAmerica stores in Minnesota and Wisconsin for about $248 million, according to documents the investor group filed Thursday with the Securities and Exchange Commission in Washington.

The stores are part of the package of 233 SuperAmericas that Marathon Oil sold in October when it sold its St. Paul Park oil refinery in a $900 million deal with ACON Investments in Washington, D.C., and TPG Capital, the buyout arm of the TPG investment company in Fort Worth, Texas.

ACON and TPG formed Northern Tier Energy LLC to operate the Minnesota assets. Northern Tier is going to lease the 135 stores from Realty Income on 15-year leases and also will pay all taxes, insurance and maintenance expenses on the properties, according to the SEC filing.

The stores average about 3,500 leasable square feet and have an average of 6.5 multi-pump gas dispensers.

Realty Income owns a diverse collection of more than 2,000 properties around the country, including 20 in Minnesota.