Feb. 2002: Ivins provided anthrax to the FBI to compare with that used in the attacks; however, authorities say the samples were unusable because he failed to follow proper protocols.
April 2002: Ivins provides another anthrax sample. Through genetic testing, it is found to be negative for the presence of the four mutations found in the anthrax used in the attacks.
December 12, 2003: An FBI special agent accompanies Ivins into the laboratory and identifies additional anthrax samples of Ivins' and others that had not been submitted previously.
April 7, 2004:
* Ivins submits the newly identified samples to the FBI.
* On this afternoon, an FBI special agent accompanies Ivins into his lab and seizes other samples that had previously not been submitted, including one known as RMR-1029.
June 17, 2004: The RMR-1029 samples seized from Ivins' lab test positive in comparison with the anthrax used in the 2001 attacks. However, the samples Ivins had submitted did not show a link.
March 31, 2005. Ivins is informed of the test results. Ivins indicates that he had been aware of the match and that he had told an FBI agent of it. The agent denies having the conversation.
May 7, 2007: Ivins tells investigators that, within three months after the letter attacks, he was aware that his stock of anthrax exhibited similarities to that used in the attacks. He says he learned this information from three co-workers at the lab who participated in the forensic analysis of the anthrax in the letters. Each of those three coworkers denies disclosing such information to Ivins.
