A federal appeals court has thrown out the conviction of Sergey Aleynikov, a former Goldman Sachs Group Inc computer programmer who had been convicted of stealing part of the Wall Street bank's high-frequency trading code.

The 2nd U.S. Circuit Court of Appeals overturned the conviction on Thursday night, and said an opinion explaining its reasoning would follow in due course.

The appeals court also directed the trial court to enter a judgment of acquittal. Generally, this means the defendant cannot be retried.

We are extremely gratified that the court of appeals refused to let this unjust conviction stand, Aleynikov's lawyer Kevin Marino said.

A call to the U.S. Attorney's office in Manhattan was not immediately returned.

The case is U.S. v. Aleynikov, 2nd U.S. Circuit Court of Appeals, No. 11-1126. The lower court case was U.S. v. Aleynikov, U.S. District Court, Southern District of New York, No. 10-00096.

(Reporting By Grant McCool and Jonathan Stempel; Editing by Gerald E. McCormick)