Tombstone are advertisements that are most often used in the financial industry, where a particular transaction, such as an offering or placement of stock

Stock

The capital stock of a business entity represents the original capital paid into or invested in the business by its founders. It serves as a security for the creditors of a business since it cannot be withdrawn to the detriment of the creditors...

 of a company, is formally announced. This is done in a form that discloses the participants in a specified order according to their role in underwriting

Underwriting

Underwriting refers to the process that a large financial service provider uses to assess the eligibility of a customer to receive their products . The name derives from the Lloyd's of London insurance market...

 or broker

Stock broker

A stock broker or stockbroker is a regulated professional broker who buys and sells shares and other securities through market makers or Agency Only Firms on behalf of investors...

ing the transaction.

In the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

, securities regulations

Securities regulation in the United States

Securities regulation in the United States is the field of U.S. law that covers various aspects of transactions and other dealings with securities...

 require that most such advertising be in the form of a tombstone format. This is in order to prevent the advertisement from being perceived as a promotion of the particular stock issue involved.

A tombstone ad is simply an announcement (not an offer) of a new security for sale. This advertisement is the only one allowed during the "cooling-off period

Cooling-off period

Cooling-off period may refer to:* Period of time after a purchase during which the purchaser has the right to return goods for a refund, or to cancel a contract without penalty...

".