A spokeswoman for El Paso tells GlobeSt.com that the move is part of a restructuring to shave costs on the bottom line. When the move's done, El Paso will have 1,300 employees working downtown and brokers scouring the market for a sublease tenant for class A space with another 11 years left on the term. The El Paso spokeswoman said the firm inherited the Greenway Plaza space three years ago when it took over Coastal Corp.

The El Paso lease generates 4.6% of the $500 million generated annually by the office building portfolio of Fort Worth-based Crescent Real Estate Equities Co. The energy giant leases 21% of the 4.3-million-sf Greenway Plaza complex, with offices scattered in 4 Greenway Plaza, 5 Greenway Plaza, 8 Greenway Plaza and 9 Greenway Plaza. Keira B. Moody, Crescent's vice president of investor relations, says 70% of the multiple leases with El Paso expire in 2014, but some come due in 2010 and 2011. And, she tells GlobeSt.com that Crescent is "looking to El Paso Corp. to fulfill its lease obligations" for the 86%-leased complex.

El Paso Corp.'s CBD holdings are the 30-story headquarters building at 1001 Louisiana St. and its neighbor, Travis Place, a two-story office building with a parking garage.