"Los Angeles Superior Court has ruled today that Anna Nicole Smith and 3-month-old baby daughter Dannielynn are ordered to submit to paternity testing," read the statement from Luck Media & Marketing Inc., released Thursday.
Smith's ex-boyfriend, Larry Birkhead, welcomed the ruling.
"Christmas has come early, and I thank God that I will soon have the opportunity to prove that I am the father ... and eventually hold her in my arms," Birkhead said in the statement.
Smith's attorney, Ron Rale, would not deny or confirm the ruling.
A Superior Court spokeswoman declined to confirm the order, saying paternity cases are confidential.
"I believe there is not an issue about Anna's willingness or unwillingness to submit to testing," Rale said. "Any kind of allegation that she's blatantly refusing DNA tests is off the mark and not an accurate depiction of the legal process at this time."
Smith was in San Francisco on Dec. 15 for a hearing in her battle for a share of the fortune left by her late husband, oil tycoon J. Howard Marshall III. It was the first time she had been back in the United States since the death of her son Daniel and the birth of her daughter in September.
Birkhead, a Los Angeles photographer, filed a lawsuit in October claiming he is the father of Dannielynn Hope Marshall Stern, who was born in September in the Bahamas.
The birth certificate lists Dannielynn's father as attorney Howard K. Stern, Smith's current companion, reports AP.
The lawsuit demands that Smith and the baby come to California for genetic testing.
Last week, Rale denied Birkhead's claim and said paternity proceedings are confidential under California law. He said parts of the case are hidden from the public and accused Birkhead's attorney, Debra Opri, of spinning the facts.