David Thomson & family

David Thomson and his family control a media and publishing empire founded by his grandfather Roy Thomson.

The family's biggest holding: more than 320 million shares of Thomson Reuters, where Thomson serves as chairman.

In 2018, Thomson Reuters announced it was selling a controlling stake in Refinitiv, a financial data provider, to Blackstone for $17 billion.

The family also holds a stake in telecom giant Bell Canada and own the Toronto-based Globe and Mail newspaper.