Offering Memorandum

What Does Offering Memorandum Mean?
A legal document stating the objectives, risks and terms of investment involved with a private placement. This includes items such as the financial statements, management biographies, detailed description of the business, etc. An offering memorandum serves to provide buyers with information on the offering and to protect the sellers from the liability associated with selling unregistered securities.

Also known as a "private placement memorandum" (PPM).

Investopedia explains Offering Memorandum
You can essentially think of the offering memorandum as a fancy business plan. In practice these are a formality to meet the requirements of securities regulators since most sophisticated investors perform their own extensive due diligence.

Offering memorandums are for private placements, while prospectuses are for publicly-traded issues.