Met Brin on a 1995 Stanford campus tour; together they built PageRank, founded Google, and later co-created Alphabet. The most consequential professional partnership of Brin's life.

Timeframe: 1995-present

A mathematician blocked from his own career ambitions by Soviet antisemitism, he made the decision to emigrate, personally home-schooled Sergey in math, and later became his professor at the University of Maryland.

Timeframe: 1973-present

Their 2007-2015 marriage connected Brin to 23andMe's genetic testing, which revealed his LRRK2 Parkinson's mutation in 2008 - reshaping the rest of his philanthropic life. The marriage ended after Brin's affair with a colleague.

Timeframe: 2007-2015

Her 1999 Parkinson's diagnosis and shared genetic mutation with Sergey drove him to become one of the largest individual funders of Parkinson's research in history, ultimately exceeding $1 billion in giving.

Timeframe: 1973-2024

Wrote the $100,000 check made out to 'Google Inc.' before the company was even incorporated, forcing Brin and Page to formalize the business.

Timeframe: August 1998

Brought in under investor pressure to provide operational leadership; the Schmidt-Page-Brin trio ran Google through its IPO and its explosive early growth years.

Timeframe: 2001-2011