When it comes to raising money to fund operations and/or strategic initiatives, companies have two basic choices (aside from just generating profits and plowing them back into the company):

　　Sell pieces of ownership of the company. Those pieces are shares of stock, and once issued, they trade on the stock market. Borrow money from investors—typically in $1,000 pieces—and pay them back with interest. Those pieces are called corporate bonds, and once issued, they trade in the bond market. Here’s how the bond market works: A bond buyer hands over money in exchange for a contract that pays regular interest (“coupons”) until maturity, when the amount borrowed (the “principal”) is returned. If the buyer wants to liquidate the investment before maturity, the bond can be sold to someone else.

　　The corporate bond marketCorporate bonds are debt securities issued by companies looking to raise money. Because they typically carry less risk than stocks (in part because bondholders have priority over stockholders in the event of bankruptcy), and because interest expenses are deductible by the company for income tax purposes, bonds have a lower cost to the issuing company than stock.

　　Data from the Securities Industry and Financial Markets Association shows that in 2022, the U.S. bond market consisted of about 66,000 corporate bond issues with a total face value of about $10 trillion. Most of these trade over-the-counter rather than on an exchange.

　　A company looking to issue bonds works with an investment banker to write and file a prospectus and to sell the bonds to investors. Bonds may be issued through a public offering or privately placed with institutional investors (e.g., pension funds, endowments, and bond funds). Many bond offerings include a variety of interest rates and maturities designed to appeal to different investors with different duration needs and risk tolerances. These different types of bonds in a single offering are known as tranches, from the French word for “slice.” Each bond comes with a contract, known as an indenture, that spells out the terms of the issue and any obligations that the company must meet.

　　Basic features of corporate bondsA corporate bond’s value at maturity is known as its face value, par value, or notional value. These words are synonyms. This value is normally $1,000. The bond pays interest, typically twice a year. Each payment is known as a coupon, because historically, bonds were pieces of paper that had coupons attached to them. When an interest payment was due, the investor would cut off a coupon and take it to the bank. Bonds have been issued electronically for the last 50 years, but the terminology lives on.

　　Coupon rates. The coupon is set when the bond prospectus is written. The market rate of interest may vary between that point and when the bond is actually sold, and it will continue to vary until the bond matures. If the market rate of interest is higher than the coupon rate, the bond will be less valuable and investors will demand a discount (to its par value) to buy it. If the market rate of interest is lower than the coupon rate, the bond will be more valuable and investors will pay a premium to par.

　　Collateral and credit. If the bond is backed by a specific piece of collateral, such as a building, then it’s known as a secured bond. Most bonds are backed only by the issuing company’s business; these bonds are known as debentures. Third-party credit rating companies assess the creditworthiness of the issue and assign a rating, similar to the credit scores that individuals receive.

　　Each rating agency has a different rubric, but in general A is better than B, which is better than C, and more letters and plus signs are better than fewer letters and minus signs. The rating may change after the bond is issued if the company’s business gets better—or worse.

　　The highest-rated bonds are known as investment-grade bonds. They generally pay the lowest coupon rates, but have the least risk. The lowest-rated bonds are known as high-yield or junk bonds. These pay high coupons and have a high risk of default.

　　Callable, convertible, and exotic bondsSome bonds have additional features that allow companies to manage their interest expense. The bond market can accommodate variety:

　　A callable bond is one that the issuer can buy back at its discretion, at predefined dates. It’s likely to do so if the interest rates on comparable bonds are considerably lower than the callable bond’s coupon rate. All else equal, investors will demand a higher interest rate for these bonds, because of the risk that they could lose those high coupons if market interest rates were to fall.Convertible bonds are bonds that can be converted into shares of stock if it becomes advantageous to do so. Convertibles generally carry lower interest rates than comparable nonconvertible bonds, in exchange for investors having the option to swap their bonds for shares of stock if the stock becomes more valuable than the bond’s par value. Convertibles tend to be issued during periods when interest rates are high and the stock market is underperforming.When a company is involved in a takeover or a corporate restructuring, different tranches of bonds may be issued with unusual features. For example, payment in kind bonds pay investors IOUs in the form of more bonds, rather than cash or shares. These issues are referred to as exotics.The bottom lineCorporate bonds are a common way for companies to raise money. Investors like them, too, because they pay predictable income and—assuming you stick to investment-grade bonds with a low risk of default—they have relatively little risk.

　　Investment pros recommend dedicating a portion of your portfolio to bonds and other fixed-income securities. Bonds tend to smooth out the volatility associated with the stock market. As you move closer to your retirement years, your portfolio may even skew in favor of bonds.

　　ReferencesUnderstanding Fixed Income Markets in 2023 | sifma.org[PDF] What Are Corporate Bonds? |sec.gov