UPDATE 1-LendingTree sues Zillow, others over Web loans

* Two patents allegedly infringed

* Patents said to help pair borrowers with lenders (Adds reactions from defendants)

NEW YORK, Sept 9 (Reuters) - LendingTree LLC has sued Zillow Inc and three other rivals, accusing them of infringing two patents for methods to help people obtain mortgage loans over the Internet.

Adchemy Inc, NexTag Inc and QuinStreet Inc (QNST.O) were also named as defendants in the lawsuit filed Wednesday in the federal court in Charlotte, North Carolina.

LendingTree, a unit of Tree.com Inc (TREE.O), accused its rivals of depriving it of profits by infringing its 2002 and 2003 patents, both titled "Method and Computer Network for Co-Ordinating a Loan over the Internet."

It said these patents allow a prospective borrower to submit a single loan application to multiple lenders, which then compete to win that borrower's business.

LendingTree obtains fees by matching borrowers with lenders, and that rival websites including Zillow Mortgage Marketplace and QuinStreet's "guidetolenders" and "hsh" sites, are improperly depriving it of such opportunities.

"The LendingTree invention has proved successful in the lending market" and resulted in "billions of dollars in loans for millions of borrowers," the complaint said.

LendingTree is seeking to recover lost profits, "but in no event less than a reasonable royalty," and other damages. It seeks a jury trial.

Zillow spokeswoman Jill Simmons declined to comment, saying the company had yet to be served with the complaint. An outside spokeswoman for QuinStreet declined to comment. Adchemy and NexTag did not immediately return requests for comment.

According to their websites, LendingTree is based in Charlotte; Zillow in Seattle; Adchemy and QuinStreet in Foster City, California; and NexTag in San Mateo, California.

Zillow also operates Zillow.com, which tracks home price changes, homeowner confidence and mortgage rates.

The case is LendingTree LLC v. Zillow Inc et al, U.S. District Court, Western District of North Carolina, No. 10-00439. (Reporting by Jonathan Stempel in New York; Editing by Bernard Orr)