San Diego, California
September 26, 2002

Diversa Corporation (Nasdaq: DVSA) today announced that it has been granted U.S. Patent No. 6,455,254, entitled "Sequence Based Screening." This patent is the first to include broad claims for discovery of novel biomolecules from the environment based upon gene sequencing of mixed populations of genomes. Sequencing-based discovery from mixed populations of organisms, such as those contained within environmental samples, has many advantages compared to single organism genome sequencing approaches, including speed, cost, and effectiveness. This novel approach complements Diversa's other proprietary methods of discovery from nature, which have produced the world's largest collection of proprietary genes identified by function.

"With this patent, Diversa has further extended its unrivaled patent position in high-throughput discovery from the environment, which includes expression-based and sequence-based methods," stated Jay M. Short, Ph.D., President and Chief Executive Officer. "Diversa is uniquely positioned to capture value from biodiversity by taking advantage of the increasing speed and cost-effectiveness of high-throughput sequencing. This patented approach will allow us to efficiently sequence mixed pools of hundreds of genomes from microbes that have never been cultured and can accelerate the discovery of novel products."

Diversa has developed an array of proprietary genomic technologies to tap the commercial potential of uncultured microorganisms, which make up more than 99% of the Earth's genetic diversity. The ability to directly sequence environmental samples and other types of mixed population samples facilitates the discovery of proteins and small molecules that have never been seen before. In addition, this patented technology can increase the speed of discovering potential commercial products relative to traditional approaches that require the isolation and purification of organisms prior to sequencing. This patent is one of a suite of patents for technologies protecting Diversa's unique abilities to discover
and evolve commercially valuable biomolecules. This patent further strengthens Diversa's patent estate, which is comprised of 68 issued patents and over 300 filed patent applications.

Diversa Corporation is a leader in applying proprietary genomic technologies for the rapid discovery and optimization of novel products from genes and gene pathways. Diversa is directing its integrated portfolio of technologies to the discovery, evolution, and production of commercially valuable molecules with pharmaceutical applications, such as optimized monoclonal antibodies and orally active drugs, as well as enzymes and small molecules with agricultural, chemical, and industrial applications. Diversa has formed significant joint ventures with The Dow Chemical Company (named Innovase LLC) and with Syngenta Seeds AG (named Zymetrics, Inc.) focused on near-term commercialization of products for the industrial and agricultural markets, respectively. In addition, Diversa has formed alliances with market leaders, such as Celera Genomics, The Dow Chemical Company, DuPont Bio-Based Materials, GlaxoSmithKline plc, Invitrogen Corporation, and Syngenta Biotechnology, Inc.