The paternity suit filed by Frances Lawrencina Anderson alleges that Soderbergh, 48, helped pay for her medical expenses during her pregnancy, and that a DNA test showed he was the father of the baby she had in August.
"(Soderbergh) has acknowledged that he is the father of the child verbally," states the lawsuit, which was filed Wednesday in a state court in Manhattan.
Anderson's lawsuit also says that she and Soderbergh had a sexual relationship at various points in 2009 when his play, "Tot Mom," opened in Sydney that December. Soderbergh's lawyer declined to comment about the lawsuit on Thursday.
Soderbergh's next film, Haywire, hits theaters in April.