The Investment Company Act of 1940 (US, 15 U.S.C. 80a)

The Investment Company Act is the US statute that governs pooled investment vehicles offered to the public — mutual funds, closed-end funds and unit investment trusts — through registration with the SEC and a dense set of structural rules. Its definition of an "investment company" (§3) is deliberately wide, which is exactly why the private-fund world is built around its exclusions (§3(c)(1) and §3(c)(7)): a fund that cannot fit an exclusion must register and accept the full regime — independent-director governance, custody of assets, strict limits on transactions with affiliates (§17), and hard limits on leverage and capital structure (§18). It pairs with the Investment Advisers Act, which regulates the manager.

Scope and the core mechanism

The Act works off the §3 definition of "investment company" and then a set of exclusions. Public funds register and live inside the regime; private funds are engineered to rely on an exclusion — most commonly §3(c)(1) (no more than 100 beneficial owners) or §3(c)(7) (only "qualified purchasers"). For registered funds the substance is structural protection of investors: a board with independent directors, custody requirements, tight controls on affiliated transactions (§17), and constraints on senior securities / leverage (§18), with daily NAV-based pricing. The full section text is searchable clause-by-clause through the regulation graph and ask-the-law.

The gotcha: for a private fund the Act is a statute you spend your time avoiding, not complying with — the whole structuring exercise is fitting a §3(c) exclusion and never stepping outside it (investor counts, qualified-purchaser status, integration). Lose the exclusion and the entire registered-fund regime lands on you at once.