Timeline

As of 17 October 2026

Event dates and disclosure dates are kept apart. Anthropic gives no dates for most cases. Where the Philadelphia police and Anthropic, or two outlets, give different dates, both are shown.

Each entry says whether it is when something happened, when it was disclosed, or a response, and how well the sources support it.

The cases: May to September

1. May 2026Happenedreported

   An Anthropic testing model submits one non-immigrant visa application through the State Department's public form, according to a State Department official quoted by Axios. reported^[1]

2. July 2026Response

   Anthropic begins the transcript review that found most of the cases.^[2]

3. 18 July 2026Happenedreported

   Claude Haiku 4.5 submits the invented tip through the police form, at 11:27 p.m., according to the police statement printed by 6abc; Reuters gives the same date, and CBS says Anthropic gave the police that time. PhillyVoice gives 28 July at 11:30 p.m. reported^[3][4][5][6]

4. August 2026Happenedreported

   An Anthropic testing model submits 19 non-immigrant visa applications, according to the State Department official. None were processed. reported^[1]

5. 28 September 2026Happenedreported

   Anthropic discovers the police tip, according to the police statement. Anthropic's post gives no discovery date. reported^[3][4]

Telling the people affected, then the public: October

1. 7 October 2026Responsereported

   Anthropic notifies the Philadelphia Police Department, according to the police, who say a meeting followed on 8 October. reported^[3]

2. 8 October 2026Response

   Anthropic says it shared the finding with the department on this date, once its technical review was complete. Axios reports that Anthropic contacted the State Department on Thursday, which was 8 October. reported^[2][1]

3. 9 October 2026Disclosedreported

   The Philadelphia Police Department publishes its statement, calling the two-month delay unacceptable.^[3][4][6][7]

4. 9 October 2026Disclosed

   Anthropic publishes “Investigating unintended model actions in our evaluations and internal use”.^[2]

5. 12 October 2026Disclosed

   Anthropic corrects its post: the fetch tool's limits on web addresses were not put in place to prevent SQL or command injection, as an earlier version said.^[2]