Boeing Co. was dealt a blow Thursday in its effort to make the NLRB’s complaint against the company go away.

Boeing Boeing facility in South Carolina.

The National Labor Relations Board judge hearing the case ruled against what he called Boeing’s “impassioned” motion to dismiss it. The NLRB has alleged that the company illegally shifted work to a nonunion factory in South Carolina from union facilities in Washington state.

“The motion to strike these allegations is without merit and should be denied,” Judge Clifford Anderson said in his 19-page ruling issued Thursday. The administrative law judge reasoned that much of Boeing’s argument couldn’t be proven at this early, “pre-evidentiary” phase of the hearing.

A Boeing spokesman said the judge’s ruling is not unexpected, since motions to dismiss are rarely granted. He also emphasized the cost Boeing and taxpayers will have to shoulder.

“As we’ve said before, the company expects to prevail in federal court on this matter, but not before lengthy and costly legal proceedings within the NLRB and, ultimately federal court,” he said.

The International Association of Machinists union, which spurred the NLRB complaint, applauded the ruling. “This reaffirms what we have said all along – that Boeing provided no facts or legal basis as to why the case should be dismissed,” a union spokeswoman said. “The case will now proceed to a trial, as it should, on its merits.”

The hearing is scheduled to resume Wednesday morning in Seattle.