Gran Tierra Energy Included in Russell 3000 Index

Gran Tierra Energy Inc. announced that it is set to join the broad-market Russell 3000 Index when Russell Investments reconstitutes its comprehensive set of U.S. and global equity indexes on June 27.

"Inclusion in the Russell 3000 Index reflects the success of our Company," said Dana Coffield, President and Chief Executive Officer of Gran Tierra Energy Inc. "Our oil exploration and development programs have resulted in reserves, production and cash flow growth over the last year and a half, resulting in a material growth in our market capitalization during that period."

Annual reconstitution of Russell's U.S. indexes captures the 4,000 largest U.S. stocks as of the end of May, ranking them by total market capitalization. Membership in the Russell 3000, which remains in place for one year, means automatic inclusion in the large-cap Russell 1000 Index or small-cap Russell 2000 Index as well as the appropriate growth and value style indexes. Russell determines membership for its equity indexes primarily by objective, market-capitalization rankings and style attributes.

The Russell 3000 also serves as the U.S. component to the Russell Global Index, which Russell launched last year.

Russell indexes 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 $4.4 trillion in assets currently are benchmarked to them. 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.