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Textbook
Introduction
1. Investment vehicle characteristics
1.1 Equity
1.1.1 Common stock
1.1.2 Trading & the market
1.1.3 Stock splits & dividends
1.1.4 ADRs & foreign investments
1.1.5 Preferred stock
1.1.6 Preferred stock features
1.1.7 Convertible preferred stock
1.1.8 Restricted & control stock
1.1.9 Tax implications
1.1.10 Fundamental analysis
1.1.11 Technical analysis
1.1.12 Cash dividends
1.1.13 Common stock suitability
1.1.14 Preferred stock suitability
1.2 Fixed income
1.3 Pooled investments
1.4 Derivatives
1.5 Alternative investments
1.6 Insurance
1.7 Other assets
2. Recommendations & strategies
3. Economic factors & business information
4. Laws & regulations
Wrapping up
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1.1.7 Convertible preferred stock
Achievable Series 66
1. Investment vehicle characteristics
1.1. Equity

Convertible preferred stock

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Convertible preferred stock allows investors to exchange their security for common stock of the same issuer. To understand this type of security, this chapter covers four subtopics:

  • Benefit to investors
  • Dilutive actions
  • Conversion logistics
  • Anti-dilution covenant

Benefit to investors

Convertibility benefits the preferred stockholder by adding another potential source of return: capital appreciation.

Preferred stock is generally treated as a fixed-income investment. It typically pays quarterly dividends, and while its market price can change, most investors don’t buy preferred stock primarily for growth. Compared with common stock, preferred stock prices tend to be less volatile and less growth-oriented.

Common stock, by contrast, is usually purchased for its growth potential. Over long periods, stock market returns have averaged around 10% annually, which can translate into meaningful capital gains. Some common stocks also pay cash dividends, so an investor who converts may still receive income.

Dilutive actions

Issuing a convertible security is a dilutive action for common stockholders because it can reduce their proportionate ownership of the company.

For example, assume you own 10 shares of a company with 100 shares outstanding. That gives you 10% ownership. Now assume the company issues convertible preferred shares that would create an additional 100 common shares if converted. If all convertible holders convert, there will be 200 shares outstanding (100 original + 100 new). You still own 10 shares, but now that’s 10/200 = 5% ownership.

Because dilution can negatively affect common stockholders, the issuer must obtain voter approval to issue convertible preferred stock or bonds.

Conversion logistics

Let’s work through examples to get comfortable with convertible preferred stock.

A $100 par, 5% convertible preferred stock with a conversion ratio of 4:1 is trading at $100 per share.

The conversion ratio tells you how many shares of common stock an investor receives upon conversion. The issuer sets the conversion ratio at issuance, and it generally stays fixed over the life of the investment. In this example, each preferred share converts into 4 shares of common stock.

Back to our example:

An investor purchases 100 shares of $100 par, 5% convertible preferred stock at $100 per share. The preferred shares maintain a conversion ratio of 4:1, while the common stock is trading at $15. A few years later, the common stock rose to $30. The investor converts their shares to common stock and immediately liquidates the position. What is the gain or loss?

Can you figure this one out?

(spoiler)

Answer = $2,000 gain

Step 1: preferred stock purchase

Purchase=# of shares x market price

Purchase=100 shares x $100

Purchase=$10,000

Step 2: convert into common shares

Conversion=pref. shares x conv. ratio

Conversion=100 shares x 4

Conversion=400 common shares

Step 3: sell common shares

Sale=# of shares x market price

Sale=400 shares x $30

Sale=$12,000

Step 4: compare the original purchase to the final sale

Return=Sale proceeds - original cost

Return=$12,000 - $10,000

Return=$2,000 gain

In that example, the investor profited because the common stock price increased. This is the core benefit of convertibility: it gives preferred stockholders a way to participate in common stock upside.

Because convertibility adds value, convertible preferred stock is typically issued with lower dividend rates than non-convertible preferred stock. Convertible securities also tend to be attractive in the market, which can push their prices higher and their yields lower (a higher price generally means a lower yield).

Conversion ratio vs. conversion price

Convertible preferred stock questions won’t always give you the conversion ratio directly. Instead, they often provide the conversion price.

The conversion price is the effective price per share of common stock if the preferred stock is purchased at par and then converted.

For example:

An investor purchases 100 shares of a $100 par, 5% preferred stock convertible at $25. What is the conversion ratio?

The formula for the conversion ratio is:

CR=Conversion pricePar ​

Using this formula, can you find the conversion ratio?

(spoiler)

Answer = 4:1

CR=Conversion pricePar ​

CR=$25$100 ​

CR=4

For every share of preferred stock owned, the investor can convert it into 4 shares of common stock. Therefore, the conversion ratio is 4 to 1.

Sometimes, questions give the conversion ratio and ask for the conversion price.

An investor purchases 100 shares of a $100 par, 5% preferred stock with a 4:1 conversion ratio. What is the conversion price?

The conversion price formula is very similar:

CP=Conversion ratioPar ​

Using this formula, can you find the conversion price?

(spoiler)

Answer = $25

CP=Conversion ratioPar ​

CP=4$100 ​

CP=$25

Preferred stock bought at par ($100) can be converted into 4 shares of common stock. That means the investor is effectively paying $25 per share of common stock ($100 / 4), which is the conversion price.

Choosing between call, sell, or convert

Now let’s apply these ideas to a more realistic decision.

An investor purchases shares of a $100 par, 7% preferred stock, which is convertible at $25 and callable at 102. A few years later, the preferred stock is trading at $103, while the common stock is trading at $26. If the issuer announces an upcoming call of the preferred stock in 60 days, which of the following options should you recommend to the investor?

A) Allow the shares to be called

B) Sell the preferred stock

C) Convert to common and sell the shares

D) Continue to hold the preferred stock

Can you figure out the best answer?

(spoiler)

Answer: C) Convert to common and sell the shares

The goal is to recommend the option that provides the greatest value. Three choices are realistic (A, B, and C). Choice D isn’t realistic because the issuer is calling the shares; holding beyond the call date isn’t a practical option.

Now compare the value of A, B, and C:

A) $102 per share

The preferred shares are callable at 102, meaning the issuer will pay 102% of par. For each share, the investor receives $102.

B) $103 per share

The call won’t occur for 60 days, so the preferred stock can still be sold in the market. The current market price is $103.

C) $104 per share

First find the conversion ratio:

  • Conversion ratio = par ($100) ÷ conversion price ($25) = 4

If the investor converts, each preferred share becomes 4 common shares. With common stock at $26, the conversion value is $104 (4 × $26).

Since choice C provides the highest value, it’s the best recommendation.

Parity price

Another way to evaluate conversion is with parity price. There are two parity prices:

  • Common stock parity price
  • Preferred stock parity price

The common stock parity price tells you the effective cost per share of common stock if you buy the preferred stock at its current market price and convert.

PP (common stock)=Conversion ratioPreferred stock market price​

An investor purchases shares of a $50 par, 4% preferred stock at $55. The shares have a conversion price of $10. What is the parity price of the common stock?

Can you figure it out?

(spoiler)

Answer = $11

First, find the conversion ratio using the conversion price:

CR=Conversion pricePar ​

CR=$10$50​

CR=5:1

Now apply the common stock parity price formula:

PP (common stock)=Conversion ratioPreferred stock market price​

PP (common stock)=5$55​

PP (common stock)=$11

So, buying the preferred at $55 and converting into 5 common shares is like paying $11 per common share.

An instant profit exists if the common stock trades above $11. For example, if the common stock is at $15, an investor could:

  • Buy 1 preferred share for $55
  • Convert into 5 common shares
  • Sell 5 common shares for $75 (5 × $15)

That’s a $20 gain per preferred share.

That “instant profit” situation is an arbitrage opportunity. In real markets, these opportunities usually last only seconds or minutes, and they’re often identified and executed by computer systems.

Here’s the same setup:

Preferred stock market price = $55

Conversion ratio = 5:1

Common stock market price = $15

To lock in the profit, an investor would typically:

  • Buy the preferred stock
  • Sell the corresponding number of common shares short at the same time

Because conversion and delivery of the common shares can take time, the short sale locks in the current common stock price. When the common shares arrive from conversion, the investor delivers them to close the short position.

Test questions may ask you to identify arbitrage. If buying the convertible, immediately converting, and selling the common stock is profitable, that’s arbitrage.

There’s one more parity price to know: the preferred stock parity price. This tells you what the preferred stock would be worth based only on the conversion feature.

PP (preferred stock)=common stock market price x conversion ratio

An investor purchases shares of a $30 par, 4% preferred stock. The shares have a conversion price of $15, while the common stock is trading at $12. What is the parity price of the preferred stock?

Can you figure it out?

(spoiler)

Answer = $24

First, find the conversion ratio:

CR=Conversion pricePar ​

CR=$15$30​

CR=2:1

Now apply the preferred stock parity price formula:

PP (preferred stock)=common stock market price x conversion ratio

PP (preferred stock)=$12 x 2

PP (preferred stock)=$24

So, based only on conversion value, the preferred stock is worth $24 (because it can be converted into 2 shares worth $12 each).

An arbitrage opportunity exists if the preferred stock trades below $24. For example, if the preferred stock trades at $20, an investor could buy it, convert, and sell the common stock for $24 - earning $4 per preferred share.

Investors use parity prices to help decide whether conversion makes sense. If conversion creates an immediate profit, an arbitrage opportunity exists.

Here’s a video that analyzes two different preferred stock parity price questions:

Anti-dilution covenant

Virtually all convertible preferred stocks are issued with anti-dilution covenants. This is the issuer’s promise to avoid diluting the value of the conversion feature.

To see why this matters, start with a situation where the conversion feature is at breakeven (parity).

Assume the following:

$100 par convertible preferred stock

Preferred stock market price = $100

Conversion ratio = 4:1

Common stock market price = $25

Here, buying the preferred at $100 and converting gives you 4 shares worth $25 each, or $100 total. There’s no gain or loss from immediate conversion.

If the common stock price rises, conversion becomes more attractive. Issuers pay attention to this because conversion creates new common shares, which dilutes the ownership percentage (and often the value) of existing common stockholders.

Without anti-dilution protection, the issuer could take actions that reduce the value of the conversion feature. Stock splits are a classic example.

Again, assume:

$100 par convertible preferred stock

Preferred stock market price = $100

Conversion ratio = 4:1

Common stock market price = $25

2:1 stock split

  • Pre-split common stock price = $25.00
  • Pre-split conversion value = $100 ($25.00 x 4)
  • Post-split common stock price = $12.50
  • Post-split conversion value = $50 ($12.50 x 4)

*Stock splits were initially covered in this chapter.

A 2:1 stock split doubles the number of shares outstanding and cuts the price per share in half. If the conversion terms don’t adjust, the conversion value is cut in half as well - from $100 to $50 in this example. That’s dilution of the conversion feature.

Anti-dilution covenants require the issuer to adjust the conversion terms when stock splits (and similar events) occur. The issuer changes the conversion price and conversion ratio so the conversion feature keeps the same economic value.

Here’s an example.

An investor purchases a $100 par, 5% convertible preferred stock with a conversion price of $50. The common stock is currently trading at $40. The issuer performs a 4:1 stock split on the common stock. What is the adjustment to the conversion price and ratio if the preferred stock contains an anti-dilution covenant?

Let’s walk through it. Start by finding the original conversion ratio.

CR=Conversion pricePar ​

CR=$50$100​

CR=2:1

So each preferred share converts into 2 common shares. With common stock at $40, the conversion value is $80 (2 × $40).

Now apply the 4:1 stock split to the common stock price:

New common stock price=Stock split factorCurrent market price​

New common stock price=4$40​

New common stock price=$10

If the conversion terms didn’t change, the investor would still receive 2 shares worth $10 each, or $20 total - far below the original $80 conversion value.

With an anti-dilution covenant, the issuer adjusts the conversion ratio and conversion price to preserve the original conversion value.

To find the new conversion ratio, multiply the original conversion ratio (2) by the stock split factor (4) (see the stock split section for how the factor is determined).

New conversion ratio=2 x 4

New conversion ratio=8

Now each preferred share converts into 8 common shares. At $10 per share, that restores the conversion value to $80 (8 × $10).

Do you know what the new conversion price would be?

(spoiler)

Answer = $12.50

You can find this two ways.

Method 1: adjust by the stock split factor

Divide the original conversion price ($50) by the stock split factor (4):

New conversion price=4$50​

New conversion price=$12.50

Method 2: use the conversion price formula with the new ratio

CP=Conversion ratioPar ​

CP=8$100​

CP=$12.50

Either method gives the same result.

Key points

Convertible preferred stock

  • Convertible into common stock of the same issuer
  • Beneficial feature for investors
  • Sold with lower dividend rates (vs. non-convertible)
    • Higher prices & lower yields

Conversion ratio

  • CR=conversion pricePar​

Conversion price

  • CP=conversion ratioPar​

Common stock parity price

  • Price paid per common share based on convertible security market price
  • PPoCS=Conversion ratioPreferred stock market price​

Preferred stock parity price

  • Value of preferred stock based only on the conversion feature
  • PPoPS=common stock market price x conversion ratio

Bond parity price

  • Value of bond based on its conversion feature
  • BPP=stock price x conv. ratio

Anti-dilution covenant

  • Prevents issuer from performing dilution actions without adjusting the conversion feature
  • Involved when stock dividends & splits occur
  • Conversion ratio goes up
  • Conversion price goes down

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