A local real estate executive is claiming $13.3 million of debt, much of it owed to unsecured creditors, in his federal bankruptcy filing.

Philo Lange, a now-independent real estate broker who once served as a top executive at two prominent Indianapolis-area firms, filed for Chapter 7 bankruptcy protection on Monday. He is former managing partner of the now-defunct NAI Olympia Partners and was managing director of the Indianapolis office of Dallas-based Trammell Crow Co.

Lange lists $793,335 in assets, including $758,000 tied to four rental homes he owns. Three are located on North College Avenue in Indianapolis and the other in Petoskey, Mich., near the Upper Peninsula of the state, according to court documents.

His total debt includes nearly $12 million in unsecured claims, in which he owes PNC Bank $5.2 million for personal guarantees on two notes to business interests Hoosier Storage-Georgetown LLC and Harbor Plaza LLC.

Lange also owes $2.1 million to Ameriserv Trust & Financial Service in Indianapolis for a loan made to NBD One LLC, in addition to a $900,000 balance on another note to NBD from Community Bank in Noblesville, court documents said.

Lange founded Lange Realty Inc. in 1981 and operated it until 1995, according to his website. He served as managing director of Trammell Crow's local office from 1996 to 2000 and then joined NAI Olympia Partners, where he eventually became managing partner.

Olympia folded in December 2010 after a 20-year run as one of the city's largest commerical real estate brokerages.

Lange did not return a phone call seeking comment about the bankruptcy.