[citation needed] Neilson first demonstrated an inclination for a future in investment management when he bought his first stock at the age of 13.

[8] In 2018, Kerr Neilson stepped down as Chief Executive Officer and was replaced by Andrew Clifford, the CIO of Platinum who adopted both roles.

[9] Platinum originated as a specialist company in international equities and continues to operate globally in 2023, with a multi-billion-dollar portfolio.

[8] The success of the company is attributed to Neilson's ability to transcend short-term market turbulence and focus on long-term returns, a philosophy that was developed over decades.

The AFR reported [13] that Argyle Fund runs a varied listed share portfolio9 with more than 100 stocks but has 85 per cent invested across the largest 60 positions.

The MSCI Total Return Index in AUD over the same time period, has delivered +9.4% p.a, highlighting Kerr's material out-performance of +7.6% p.a.

By comparison the Australian All Ordinaries Index fell 13.3% [19] (The fiscal year of 1988 including the 20 October 1987, fall of 25%, its largest one-day loss ever).

In another difficult period in global markets post the tech boom of 2000, the Platinum International Fund rose by 59% from 2000 to 2003, whilst the MSCI fell by 31% in total.

[23] Two booklets have been published by Platinum Asset Management, titled Reflections on Investment and Curious Investor Behaviour.

In the foreword Neilson says that investing leans heavily on common sense, which is both a prop and a hindrance to the learning process.