Assets Under Management (AUM)

What it is:

Assets under management (AUM) refers to the total market value of investments managed by a mutual fund, money management firm, hedge fund, portfolio manager, or other financial services company.

How it works/Example:

AUM generally changes according to the flow of money into and out of a particular fund or company. It also fluctuates based on changes in the value of a fund or company's underlying investments.

Why it Matters:

SEC guidelines leave room for interpretation on what may be included in AUM, but there are at least two important reasons why investors should be sure to understand an asset manager's method of calculating AUM.

First, investors are entitled to fair and transparent disclosure of an asset manager's true performance over time. Because many asset management companies compare the size of their AUM with competitors as a measure of success, accurate disclosure is especially important for correctly evaluating an asset manager's performance.

The CFA Institute has established ethical standards -- called the Global Investment Performance Standards (GIPS) -- that are especially useful to individual investors. The GIPS standards are a set of standardized, industry-wide ethical principles that provide investment firms with guidance on how to calculate and report investment results to prospective clients. Firms must comply with the CFA Institute's high ethical standards if they want to prepare their marketing materials according to GIPS (and advertise their compliance).

Second, many asset management companies charge management fees that are equal to a fixed percentage of AUM, making it especially important for investors to understand how the firm calculates AUM.

Best execution refers to the imperative that a broker, market maker, or other agent acting on behalf of an investor is obligated to execute the investor's order in a way that is most advantageous to the investor rather than the agent.