The sign strung from the rafters of U.S. Bank Stadium by daredevil protesters Sunday had a short message: "DIVEST," it read, followed at the bottom by "#NoDAPL."

The bottom is a reference to the Dakota Access Pipeline project – that crude oil pipeline that was supposed to run near the Standing Rock Sioux Reservation in North Dakota, but was blocked by the federal government after months of protests. But what exactly are the protesters asking for?

U.S. Bank and the Dakota Access Pipeline

The company that's trying to complete the Dakota Access Pipeline is Energy Transfer Partners, which is based in Texas and operates thousands of miles of pipeline across the U.S.

The company, naturally, gets credit lines and loans from financial institutions such as banks. Which is where this whole divest thing comes from.

U.S. Bank is one of the (many) banks that's reportedly given loans and lines of credit to Energy Transfer Partners, according to an investigation detailed by the website LittleSis.

LittleSis in August identified U.S. Bank as having provided a $175 million credit line to Energy Transfer Partners. (It's not clear exactly how that money may have been used – for example, Royal Bank of Scotland said it had provided general financing to the pipeline builders, but didn't fund the Dakota Access Pipeline.)

U.S. Bank is one of 26 banking institutions that, in total, provide a revolving credit line of $3.75 billion to the pipeline company, according to LittleSis.

U.S. Bank however is not one of the large players in the gas and oil industry. LittleSis says six banks – JPMorgan Chase, Morgan Stanley, Goldman Sachs, Wells Fargo, Bank of America and Citibank – have lent a total of $200 billion to the industry.

'Divest'

What the protesters during the Vikings game Sunday want is for U.S. Bank – which is based in Minneapolis and has its name on the stadium – to remove itself from offering credit lines to Energy Transfer Partners.

“We are here in solidarity with water protectors from Standing Rock to urge US Bank to divest from the Dakota Access Pipeline," said one of the two climbers, Sen Holiday, in a statement from the Minneapolis #NoDAPL group.

It's the same thing larger groups have been calling for for months now.

Defund DAPL has been asking people to take their money out of banks that support the pipeline companies, and also tell the bank why via a letter or call. According to their tracker (which is based on self-reporting, keep in mind) nearly $42 million has been withdrawn from banks so far.

U.S. Bank didn't comment on Sunday's stadium protest when asked by outlets such as CNN. A spokesperson for the Standing Rock Indian Reservation though told CNN the climbers weren't part of their protest.

You can read more about the broader effort targeting banks here.