Fixed mortgage rates were mostly unchanged this week as credit markets showed little reaction to Washington's impasse over raising the federal government's borrowing limit.

Freddie Mac reported Thursday that the average rate on the 30-year fixed loan ticked up to 4.55 percent from 4.52 percent a week ago. That's slightly above this year's low of 4.49 percent.

The average rate on the 15-year fixed loan was unchanged at 3.66 percent, just above the yearly low of 3.65 percent.

Mortgage rates typically track the yield on the 10-year Treasury note. Yields have been stable, even though Congress and the Obama administration are days away from a potential default on the government's debt.

Low mortgage rates and depressed home prices have done little to revive the struggling housing market. Many people simply can't take advantage of the historically low rates because of tighter lending standards and bigger required down payments.

The number of homes taken back by lenders in the first half of this year fell 30 percent compared with the same 2010 period, the result of delays in foreclosure processing that threaten to stall a U.S. housing recovery.

Banks seized 421,212 homes in the first six months of the year, down from 529,633 between January and June last year, foreclosure listing firm RealtyTrac Inc. said Thursday.

The decline reflects lenders taking longer to move against homeowners who have fallen behind on their mortgage payments. The banks are working through foreclosure documentation problems that first surfaced last fall and an ensuing logjam in some state courts. Lenders also have put off on taking action against delinquent borrowers as U.S. home sales have slowed this year.

As the processing delays mount, however, so has the backlog of potential foreclosures -- homes that otherwise would have been repossessed by lenders this year.

RealtyTrac estimates that 1 million foreclosure-related notices that should have been filed by banks this year will be pushed to next year. The filings include notices for defaults, scheduled home auctions and home repossessions -- warnings that can lead to a home eventually being lost to foreclosure.

The Supreme Court has refused to get involved in a long-running dispute on the continued existence of the Yankton Sioux Tribe and the extent of its lands in South Dakota.

The justices on Monday let stand several rulings involving the tribe, including an appeals court decision saying the reservation covers more than 30,000 acres, which is mostly land the federal government holds in trust for the tribe and individual tribal members.

The high court also rejected an appeal from the tribe to block the transfer of two federal recreation areas along the Missouri River to the state of South Dakota.

The cases are Daugaard v. Yankton Sioux Tribe, 10-929; Southern Missouri Recycling v. Yankton Sioux Tribe, 10-931; Hein v. Yankton Sioux Tribe, 10-932; and Yankton Sioux Tribe v. Daugaard, 10-1058.

Before Donald Trump sold the idea of a possible 2012 presidential bid, the bombastic real estate mogul peddled the American dream at a place called Trump University. He promised consumers the golden opportunity to be "my next apprentice" and learn "insider" secrets of real estate.

But a lawsuit filed in U.S. District Court in San Diego claims that the possible GOP presidential candidate's courses instead delivered expensive "infomercials" disguised as educational classes that preyed on vulnerable Americans in "troubled economic times."

George Sorial, assistant general counsel for the Trump Organization, told The Chronicle this week that the allegations contained in the suit are "completely ridiculous," adding that Trump University stands "100 percent behind any course we offered."

Sorial dismissed the lawsuit as an effort by two former students and their attorneys "looking to make a quick buck" from the celebrity businessman.

"There wouldn't even be a lawsuit if the Trump name weren't attached to it," he said.

But Tarla Makaeff, 37, a former fashion designer and marketer from Corona del Mar (Orange County), told The Chronicle in an interview this week that Trump's "university" was hardly worthy of the name.

The federal government has sued Deutsche Bank. It alleges the bank committed mortgage fraud by repeatedly lying so that it could join a government program that insured mortgages.

The Manhattan lawsuit seeks to recover some of the hundreds of millions of dollars in insurance claims that the government has had to pay when homeowners defaulted on their mortgages. The lawsuit also asked for punitive damages.

According to the lawsuit, Deutsche Bank profited from the resale of the government-insured mortgages.

The government says Deutsche Bank recklessly selected mortgages that violated the rules of the program. It says the bank ignored whether borrowers could afford their mortgage payments.

Deutsche Bank says in a statement that it will fight the lawsuit. It calls the allegations "unreasonable and unfair."

Iowa A hasty mortgage approval has led to an almost-free house for an Ankeny couple.

Matt and Jamie Danielson own their $278,000 Ankeny home outright after making one payment to the lender and winning a court fight waged over a 123-year-old Iowa law.

The law's original intent was to protect a husband or wife from the foolishness or evil intent of a spouse. It requires the voiding of mortgages that aren't signed by both spouses. The Des Moines Register says Jamie Danielson didn't sign when she and Matt bought the home in May 2007.

They moved in, made one payment and then his business went under. They went to their attorney to file bankruptcy. He noticed that Jamie's signature was missing from mortgage documents, so he took their case to court.

A law firm that once led Florida in foreclosures is shutting down amid an investigation into "robo-signing" and other questionable practices.

A Securities and Exchange Commission filing Monday indicated that David Stern's Plantation-based practice will end operations March 31. The firm once had more than 1,200 employees and handled tens of thousands of foreclosures each year.

Stern's firm is one of several under investigation by Florida's attorney general. The probe focuses on whether false or improper affidavits were filed in foreclosures and whether employees were robo-signers who signed documents without reading them.

A broader national probe is examining how foreclosures were handled during the economic downturn.