EXHIBIT 10.12 UNDERTAKING TO COMPLY WITH CERTAIN PROVISIONS OF OPTION AGREEMENT This Undertaking (this "Undertaking") is entered into as of August 31, 2002 by Texas Genco Holdings, Inc., a Texas corporation ("Genco"). WHEREAS, Reliant Energy,...Undertaking to Comply With Certain Provisions of Option Agreement • November 26th, 2002 • Texas Genco Holdings Inc • Electric services
