David and Simon Reuben

As of 2016[update], their business activities mainly involved real estate, both in the UK and abroad, venture capital, and private equity.

[6][dead link‍] In 2006, the Reuben Brothers formed a partnership that injected private equity into the FTSE-listed McCarthy & Stone, a retirement home construction company, exiting from that investment in 2013.

[14][failed verification] The Reuben Brothers invested in luxury leisure group Belmond Ltd in 2007, and sold their share in 2019 for £233 million.

[6][dead link‍] On 14 April 2020, it emerged that a deal to transfer ownership of Newcastle United Football Club had been agreed between incumbent owner Mike Ashley and a prospective buying consortium consisting of Reuben Brothers, Amanda Staveley's PCP Capital Partners, and the Public Investment Fund of Saudi Arabia.

[17][18] On 7 October 2021, the Premier League approved the buy-out, stating that it has "received legally binding guarantees that the Kingdom of Saudi Arabia will not control the Newcastle United club".

[22] On 19 August 2024, Reuben Brothers acquired a strategic stake in EDGLRD, an entertainment company founded by filmmaker Harmony Korine.

Livingstone controversially told the media conference, referring to the Reuben brothers, that "If they're not happy here, they can go back to Iran and try their luck with the ayatollahs, if they don't like the planning regime or my approach."

Conservative members of the London Assembly stated the brothers were not Iranian, but had been born in British India of Iraqi-Jewish parents.

[28] According to the Sunday Times Rich List 2023, David and Simon Reuben and their combined family had an estimated net worth of £24.4 billion.