By Grant McCool

The claims, to be made through the non-profit Securities Investor Protection Corporation (SIPC) and a court-appointed trustee, are just one avenue for investors who believe they were duped in Madoff's purported $50 billion fraud.

Some investors have filed lawsuits, many of them against the hedge funds who entrusted money to Bernard L. Madoff Investment Securities LLC.

Madoff, a former chairman of the Nasdaq stock market, was arrested and charged on December 11, with securities fraud. He is under house arrest in his Manhattan apartment.

"Claimants are requested to provide complete information and documentation relating to their claim, including proof of payments made to BLMIS and received from BLMIS, as this may help to expedite the processing of the claim," said the statement by SIPC, a group established by Congress in 1970 to maintain a reserve fund for investors at failed brokerages.

"The trustee is proceeding as expeditiously as possible to address the claims of all of the customers of BLMIS in a timely manner," according to the joint statement by SIPC and the court-appointed trustee, lawyer Irving Picard.

Picard has asked a U.S. bankruptcy judge in New York for subpoena powers to gather evidence and interview witnesses.

Madoff, 70, is accused in parallel criminal and civil investigations after authorities said he admitted to running a scheme over many years that apparently bilked the wealthy, banks, charities and funds all over the world. No one else has been charged.

The law that created SIPC provides that customers of a failed brokerage firm receive all non-negotiable securities -- such as stocks or bonds -- that are already registered in their names or in the process of being registered.

Funds from the group's reserve are available to satisfy the remaining claims of each customer up to a maximum of $500,000, including a maximum of $100,000 on claims for cash.

Monday's statement said more than 8,000 customer claim forms were mailed on January 2, with deadlines of March 4 and July 2 for filing them with the trustee.

The notice, claim forms and related information are available on the websites http://www.madofftrustee.com and http://www.sipc.org.

(Editing by Maureen Bavdek)