"We have filed a petition. Now it's in the court's hands,” Talwar's lawyer Rebecca John told IANS.
"I would not comment on the merits of the case as the case is subjudice,” John added.
Special Judicial Magistrate Preeti Singh had ordered Feb 9 that the Talwars be charged with murder, destruction of evidence and criminal conspiracy.
"We are definitely taken aback by the order. Nothing can justify the summoning of Rajesh Talwar (for the next hearing Feb 28) but having done it, we will go to a higher court challenging the order," John had said earlier.
Aarushi, a Class 9 student of Delhi Public School, Noida, was found murdered under mysterious circumstances in her parents' Jalvayu Vihar Apartment in Noida on May 16, 2008.
Their domestic help Hemraj was initially suspected for the killing, but his body was found on the flat's terrace a day later.