High School

A company has issued convertible bonds with a face value of $1000 and a conversion ratio of 40. The company also has equivalent non-convertible 'plain' bonds. From the point of view of the issuer, which of the following would represent an equivalent portfolio to a single convertible bond?

A. Short a plain bond and write 25 call options with a strike of 40
B. Short a plain bond and buy 40 call options with a strike of 25
C. Short a bond and write 40 puts with a strike of 25
D. Short a bond and write 40 calls with a strike of 25
E. Buy 40 shares and 40 puts with a strike of 25

Answer :

To understand which portfolio equates to a single convertible bond from the issuer's perspective, we need to break down the components involved.

  1. Convertible Bond: This is a type of bond issued by a company that can be converted into a predetermined number of shares. In this case, the conversion ratio is 40, meaning each bond can be converted into 40 shares of stock.

  2. Equivalence in Options Terms: The equivalence of a convertible bond usually involves both debt and equity components:

    • Debt Component: The non-convertible plain bond part.
    • Equity Component: Options that reflect the rights to convert the bond into equity.

To replicate this with options and a non-convertible bond:

  • By holding the equivalent plain bond, any deviation must relate to the equity conversion.
  • You would offset the bond position by shorting a plain bond.
  • Then, you add a derivative position that matches the conversion feature.

  1. Breaking Down the Options: Let's analyze each choice:

    a. Short a plain bond and write 25 call options with a strike of 40 - This does not match the equity conversion aspect because writing 25 call options at a higher strike price doesn't accurately cover the conversion ratio or its market scenario.

    b. Short a plain bond and buy 40 call options with a strike of 25 - Buying calls reflects the control to convert into shares. However, the strike price does not directly align with the conversion ratio.

    c. Short a bond and write 40 puts with a strike of 25 - Writing puts does not align well with the equity feature of convertible bonds, as they provide a different payoff scheme.

    d. Short a bond and write 40 calls with a strike of 25 - This option mirrors the equity feature of a convertible bond but in reverse because writing a call implies the opposite of holding the conversion right.

    e. Buy 40 shares and 40 puts with a strike of 25 - Buying shares somewhat covers the equity position upon conversion, but adding puts alters the payoff structure.

From the issuer's perspective, the most directly matching option is d. Short a bond and write 40 calls with a strike of 25. This mirrors a counter-position where the issuer covers the conversion feature with calls written at the conversion price, aligning the obligation upon conversion.

Chosen Option: d. Short a bond and write 40 calls with a strike of 25.

This way, the combination of shorting the bond (reflecting the removal of principal guarantee) and writing calls (offsetting the conversion feature) represents a close replication to issuing a convertible bond from the issuer's viewpoint.