BMO Harris Bank

Disclosed Mar 17, 20179 years ago38,391 affectedConfirmed

Official notice

What is known

People affected	38,391 (as reported by the organization)
Disclosed	Mar 17, 2017
Discovered	May 17, 2017
Happened	May 15, 2017
Attack	Not stated
Data exposed	Not stated
Sector	Finance · US
Status	Confirmed

Sources

Source	Kind
California Attorney General breach notice: BMO Harris Bankoag.ca.gov · Official notice	Official notice
Oregon DOJ breach notice: BMO Harris Bankjustice.oregon.gov · Official notice	Official notice
Indiana Attorney General 2017 data breach report: BMO Harris Bankin.gov · Official notice	Official notice

Notices filed

Where	Filed	People
Indiana AGresidents of IN	Mar 17, 2017	1,201
California AGresidents of CA	May 31, 2017
Oregon DOJresidents of OR	May 31, 2017	38,391
Indiana AGresidents of IN	May 31, 2017	1,726

Other breaches at BMO Harris Bank

Breach	Disclosed	Attack	Sector	Status	Affected
Disclosed Oct 23, 2015Oct 23, 201510 years ago	Oct 23, 201510 years ago	Not stated	Finance	Confirmed	2

History of this record

2026-09-25 · records_basis: empty to organization · backfill source
2026-09-25 · records: empty to 38391 · backfill source
2026-09-25 · disclosed: 2017-05-31 to 2017-03-17 · backfill source
2026-09-25 · discovered: empty to 2017-05-17 · backfill source
2026-09-25 · added · backfill source

First seen 2026-09-25 (California AG), confirmed by California AG. Record counts are as reported. Not legal advice.

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