That alleged conversation would have occurred at roughly the same time that Aurora Police Chief Dan Oates said Holmes began receiving "a high volume of deliveries" at his home and at the university. Authorities have not said what those packages contained, but they said he ordered thousands of rounds of ammunition on the Internet.
The prosecution's allegation is the earliest report of a possible threat from Holmes, who was an enigma to many before authorities said he opened fire on a midnight showing of "The Dark Knight Rises" on July 20. Twelve people were killed and 58 were wounded.
Prosecutors said Holmes left the neuroscience program in June after also making unspecified threats to a professor and failing his year-end final, both in that month.
Holmes' attorneys argue that prosecutors should have no access to his student records. It's not clear whether Holmes' attorneys filed a response to the alleged threats. Most filings in the case are sealed and none of the defense filings released Friday by the judge address the alleged threats.
The prosecution motion was filed last week but only released by the judge on Friday, a day after a court hearing in which prosecutors first asserted that Holmes had made threats. They didn't disclose any details about the threats in court.
Prosecutors, defense attorneys and a spokeswoman for the University of Colorado didn't immediately return calls seeking comment.
Holmes' defense lawyer, Daniel King, has said Holmes is mentally ill and was seeing a psychiatrist at the university, setting up a possible insanity defense.
But arguments at Thursday's hearing by Chief Deputy District Attorney Karen Pearson revealed a possible motive: Holmes' anger that he was failing at school, "at the same time he's buying an enormous amount of ammunition, body armor and explosives."
A gag order has been issued in the case. Prosecutors argued that gaining access to the school records would establish a motive by showing what Holmes hoped to accomplish at CU and the "dissatisfaction with what occurred in his life that led to this."
They also want to see records from campus police and a campus threat evaluation team similar to those established across the country after the 2007 Virginia Tech University shootings.