Cellectis Terminates Genoway's License under Its Homologous Recombination Technology.

ROMAINVILLE, France -- Biocitech - Cellectis S.A. (NYSE - Euronext: ALCLS), the genome engineering company, announces having terminated the non-exclusive license it had granted to Genoway S.A. in 2001 for certain uses of homologous recombination. The termination is effective as of December the 30th 2008.

The license was granted under patents: FR2646438, EP419621, EP682112, US6528313, US6638768, US6528314, JP3059481, JP3298842, JP3298864, SG49110 and SG49112, and authorized making and selling cellular and animal models in a restricted field, for research uses only expressly excluding the use of such product for any commercial application.

Genoway S.A. challenged this termination in court. Cellectis intends to obtain proper compensation for the damages that it deems having suffered from the uses made by Genoway S.A. outside the licensed field.

About the licensed patents

The license granted rights under a patent family deriving from the original FR8903630 filing dating back to 1989. This family includes patents: FR2646438, EP419621, EP682112, US6528313, US6638768, US6528314, JP3059481, JP3298842, JP3298864, SG49110 and SG49112. The last patents to expire in that family will expire in 2020 in the USA. Institut Pasteur granted Cellectis with the exclusive worldwide rights over this patent family.

These patents cover certain uses of homologous recombination (also referred to as "gene targeting"), in particular for the targeted insertion of DNA sequences made functional in eukaryotic genomes, such as that of animals for example. The "knock-in" processes, currently used to obtain cellular and animal models, including mouse models, such as mice that are "humanized" for a chosen gene, are covered by these patents, which use bring significant benefits to the pharmaceutical and biotechnology industries for the understanding of biological mechanisms as well as for drug development.

About Cellectis S.A.

Cellectis SA (www.cellectis.com) is a world leader in genome engineering and genome surgery. The company focuses on developing and producing custom meganucleases for use in vivo genome surgery addressing the therapeutic, agricultural biotechnology, biomanufacturing and research sectors. Worldwide, Cellectis has entered into more than 50 agreements with major players in the pharmaceutical, biotech and agricultural biotechnology industries and has over 20 collaborations with academic research groups. Since its incorporation, Cellectis has raised over 50 million in both equity operations and public financing and is listed on the NYSE-Euronext Alternext market (ticker code: ALCLS). For more information on Cellectis, visit our website: www.cellectis.com

Disclaimer - This press release contains forward-looking statements that relate to the Company's objectives. Such forward-looking statements are based on the current expectations and assumptions of the Company's management only and involve risk and uncertainties. Potential risks and uncertainties include, without limitation, whether the Company will be successful in implementing its strategies, whether there will be continued growth in the relevant market and demand for the Company's products, new products or technological developments introduced by competitors, and risks associated with managing growth. Unfavorable developments in connection with these and other risks and uncertainties described, in particular, in the Company's prospectus prepared in connection with its IPO and on which the French Autorite des marches financiers ("AMF") granted its visa nx 07-023 on January 22, 2007, could cause the Company to fail to achieve the objectives expressed by the forward-looking statements above.