Who are the five families in London?

The biggest prop firms, known as “the five families,” were based in London and had dozens of traders on their books, many of whom had come from the pits.

For a long time, Commins and much of his crew traded as an off-site offshoot of Tower Trading Group, one of the five families.

I am guessing GHF who are mentioned in the article are one. Who else?

Negative Oil: When Prices Went Below Zero, These Essex Traders Made Millions - Bloomberg

 

why does it matter?

 

I live in London. ABCD in commodities is Archer Daniels Midland, Bunge, Cargills, Dreyfus.

 

Continental Grain as well in the Old Days. Good book on the topic "Merchants of Grain"

 

I trade with ADM UK options