By Blake Brittain

(Reuters) -A Delaware jury on Friday ordered Illumina Inc to pay more than $333 million to a U.S. unit of Chinese genetic analysis company BGI Genomics after finding that Illumina’s DNA-sequencing systems infringed two patents.

The jury also said Illumina infringed the patents willfully, and that three patents it had accused BGI’s Complete Genomics unit of infringing were invalid.

BGI and Illumina are both major providers of genome-analysis technology used to detect genetic diseases. The companies have been embroiled in a global legal battle over their respective sequencing technologies, with court cases in countries including Germany, Denmark, Switzerland, and Turkey.

Illumina’s stock was down more than 14% Friday following the verdict.

Illumina previously won $8 million from BGI in a jury verdict in San Francisco and a ban on U.S. sales of some BGI products.

In the Delaware case, San Jose, California-based Complete Genomics Inc, a BGI subsidiary, had challenged Illumina’s “two-channel” sequencing systems and kits to prepare DNA fragments for sequencing of violating its patent rights.

An Illumina spokesperson said the company plans to appeal and that the verdict should not affect its ability to supply its customers.

An attorney for Complete Genomics said the company was pleased with the award, which the judge could multiply based the jury’s finding of willful infringement.

Illumina also said Friday in a filing with the U.S. Securities & Exchange Commission that it may have to pay interest and an ongoing royalty until the patents expire in 2029 if it loses on appeal.

(Reporting by Blake Brittain in Washington; additional reporting by Raghavi Kasa; Editing by David Gregorio and Diane Craft)