A Warner Bros. spokeswoman told The Denver Post that Bale was representing himself, not the movie studio.
Bale, who stars as Batman in "The Dark Knight Rises," previously issued a written statement saying: "Words cannot express the horror that I feel. I cannot begin to truly understand the pain and grief of the victims and their loved ones, but my heart goes out to them."
President Barack Obama and members of the Denver Broncos also have made hospital visits to some of the survivors.
Bowman-Hayes and her staff cared for patients at both Swedish Medical Center and The Medical Center of Aurora after the shootings, whether it was in the operating room or intensive care unit, or by washing medical instruments.
She said the staff appreciated Bale's visit.
"He did this out of his heart, and you could really tell. It was so sincere," she said. "It was just, 'thank you.'"