The Exploration Company Joins Russell 3000 Index

The Exploration Company reported that it has been added to the Russell 3000® Index by the Russell Investment Group.

Membership in the Russell 3000, which remains in place for 1 year, means automatic inclusion in the large-cap Russell 1000® Index or small-cap Russell 2000® Index as well as appropriate growth and style indices. Russell determines membership for its equity indices primarily by objective, market capitalization rankings, and style attributes.

"We welcome the additional exposure to index-oriented institutions afforded by inclusion in the Russell 3000 and other Russell indices," said TXCO President and CEO James E. Sigmon. "Our continued Maverick Basin growth over a number of years has allowed us to achieve this milestone and we look forward to continuing that history of growth and increasing shareholder value in 2006 and beyond."

Russell indices are widely used by investment managers and institutional investors for index funds and as benchmarks for both passive and active investment strategies. An industry-leading $3.8 trillion in assets currently are benchmarked to them. Investment managers who oversee these funds purchase shares of member stocks according to a company's weighting in a particular index.

Annual reconstitution of Russell indices captures the 3,000 largest U.S. stocks as of the end of May, ranking them by total market capitalization to create the Russell 3000. The largest 1,000 companies in the ranking comprise the Russell 1000 while the remaining 2,000 companies become the widely used Russell 2000. These investment tools originated from Russell's multi-manager investment business in the early 1980s when the company saw the need for a more objective, market-driven set of benchmarks in order to evaluate outside investment managers.

Russell, a global leader in multi-manager investment services, provides investment products and services in 44 countries. Russell manages more than $167 billion in assets and advises clients worldwide representing $2.4 trillion. Founded in 1936, Russell is a subsidiary of Northwestern Mutual and is headquartered in Tacoma, Wash., with additional offices in New York, Toronto, London, Paris, Singapore, Sydney, Auckland, and Tokyo.

The Exploration Company is an independent oil and gas enterprise with interests primarily in the Maverick Basin of Southwest Texas and the Marfa Basin in West Texas.