USS stands for Universities Superannuation Scheme. It is the largest private pension scheme in the country in terms of assets. Established in 1974, it is the principal pension scheme for universities and higher education institutions in the UK.
USS is the pension scheme itself, and Universities Superannuation Scheme Limited is the trustee that runs and manages USS. USS Investment Management Limited is the subsidiary that looks after the investment management of the assets of £67.6 billion ($90 billion) at the end of March 2020.