A judge in Nantucket, Mass., Ordered the three to hand over the phone so defense specialists could examine him.
Spacey's lawyers argued at a hearing earlier this month that evidence that could exonerate the 59-year-old actor was erased from the phone before being handed over to prosecutors.
"(The accuser) and his family do not remember seeing the issue after December 2017, when the phone was delivered to the Commonwealth," Mitchell Garabedian, a family lawyer, wrote in court documents. "(The accuser) and his family searched all the places where this phone may have been stored. They did not find the phone."
CNN is not naming Spacey's accuser because he is a suspected victim of sexual assault.
Spacey is accused of indecent assault and battery for allegedly groping an 18-year-old waiter's helper in July 2016 at the Club Car bar on Nantucket Island.
During the alleged assault, the accuser sent text messages on his phone, including a video less than a second long, to his girlfriend.
Prosecutors told Judge Thomas Barrett last month that they obtained a copy of the phone data, but the device was returned.
A CD containing the files obtained from the phone was delivered to defense lawyers, but they say that was not enough.
"Access to the underlying databases is necessary to conduct a proper analysis, including whether messages may have been deleted or attempted to recover deleted data," defense expert Sankara Shanmugam wrote in a statement.
Spacey's lawyers have discussed screen shots and a police report has left no questionable evidence has been deleted, and they should be allowed to try to retrieve it.
"He and his mother have deleted the texts of excuses that were on the phone," defense lawyer Alan Jackson told a hearing this month. "They deleted information they did not want the police to have, they deleted information they did not want us to have."
Garabedian wrote in today's paper that police notes say the phone was returned to the accuser's father, but "he has no memory of receiving the son of the police."
As the phone can not be found, Garabedian says they are trying to find backups of what was in it.
"Understanding the meaning of this order, (the accuser) and his family are in the process of hiring a digital forensic expert to look for probable telephone (prosecutor) 2015 backups."
In response to Garabedian's filing, Judge Barrett has extended the deadline to deliver the phone until July 8.
If the phone is not found by then, the accuser, his mother and his lawyer must appear in court to testify about his whereabouts.