Harland Hammerstein was an employee of Abstergo Industries. In December 2010, Hammerstein noticed several missing Animus blueprints from the Animus Project. Realizing that nobody was paying attention to his questions about it, Hammerstein started looking deeper into the matter, eventually finding the codeword "Project Siren". He speculated that it was related to Subject 17, and that Warren Vidic or Lucy Stillman was behind the leak. He sent an email to Erica Nichols with his findings and asked her if she had more information for him.