Beckman and partner Orchid sue Sequenom

Genetic and molecular diagnostic company Sequenom Inc. said Monday it is being sued over its iPLEX DNA analysis system by Beckman Coulter Inc. and Orchid Cellmark Inc.

Fullerton, Calif. based Beckman and Princeton, N.J.-based Orchid, which both make biomedical instruments and testing equipment, filed the lawsuit in the U.S. District Court of the Southern District of California. In a Securities and Exchange Commission filing Monday, San Diego-based Sequenom said it is being accused of patent infringement.

Beckman and Orchid are asking for a permanent injunction barring the sale of iPLEX products along with unspecified money damages.

Shares of Sequenom fell 53 cents, or 4.1 percent, to $12.30 in after-hours trading after rising 96 cents, or 8.1 percent, to close at $12.83 during the regular trading session.

Meanwhile, Beckman shares fell 1 cent to $69.65 in after-hours trading after falling 29 cents to close at $69.66 during the regular trading session. Orchid shares fell 11 cents, or 3.6 percent, to close at $2.97.