NEW YORK — Luigi Mangione, the alleged CEO murderer, recently turned 27, celebrating by sending out a list titled “27 Things I’m Grateful For” to those who have been in correspondence with him during his incarceration. This list is now spreading online.

Mangione reportedly receives a significant volume of mail daily—anywhere from 10 to 115 letters, according to his lawyers—resulting in what he describes as a “bizarre and disorienting Groundhog Day scenario where every day feels like both Christmas and my May 6th birthday.”

The accused wrote that letters have arrived from over 40 different countries and that he’s been sent “countless books,” including works like Ayn Rand’s “Anthem” and Ray Bradbury’s “Fahrenheit 451,” filling up the “birdcage” he shares with his cellmate, referred to as “J.”

Mangione has pleaded not guilty to state and federal charges stemming from the assassination-style shooting death of United Healthcare chief executive Brian Thompson. His next court appearance is scheduled for June 26, at which Judge Gregory Carro could set a trial date.

“If ever there were an open and shut case pointing to defendant’s guilty, this case is that case. Simply put, one would be hard pressed to find a case with such overwhelming evidence of guilt as to the identity of the murderer and the premeditated nature of the assassination,” Joel Seidemann, an assistant district attorney in Manhattan, wrote in a recent court filing. “While this is of no solace to Mr. Thompson, his family or his friends, the assassination was not personal to Mr. Thompson but rather a necessary part of defendant’s evil plan to usher revolutionary changes to the delivery of healthcare in the United States through the barrel of a gun.”

Mangione has sought to dismiss or delay the state case to concentrate on the federal case, which could yield the death penalty.