Trading Calculators
Rights Offering & CB Dilution Calculator
Calculate how much your ownership and the share price are diluted when a rights offering or CB conversion occurs.

Enter your values and press Calculate
Share count dilution
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Theoretical price (ex-rights)
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Change in my ownership
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Change in my holding value
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Dilution risk
When a filing appears, calculate first
Rights offerings and CB conversions increase the share count and shrink existing shareholders' slice. The lower the issue price relative to the current price, the bigger the price dilution.
Enter the filing numbers
Enter the existing total shares outstanding, new (conversion) shares and issue (conversion) price from the DART filing (DART, the FSS electronic disclosure system).
Enter your holdings
Enter your share count to see the change in ownership and value.
Whether you subscribe
For a shareholder-allocated offering, compare how the result differs depending on whether you subscribe.
The actual ex-rights reference price is set by the exchange using a separate formula, and market prices vary with supply and demand and the intended use of proceeds. Note that with CB/BW conversion, only the share count rises, with no new money entering the company (bonds already issued are swapped into shares). You can check conversion schedules in the CB/BW Conversions calendar.
FAQ
What happens if I don't take part in a shareholder-allocated rights offering?
If you don't exercise your subscription right, your ownership is diluted, and the ex-rights adjustment can theoretically lower the share price and reduce your holding value. Selling the subscription rights certificate can recoup part of it.
Why does CB conversion weigh on the share price?
When the share price is above the conversion price, bondholders can convert into shares and sell for a profit. When those shares hit the market they create selling pressure, which is called an overhang.
What is refixing (conversion price adjustment)?
It is a clause that lowers the CB conversion price when the share price falls. A lower conversion price increases the number of conversion shares and makes dilution larger.
Results are estimates based on your inputs and simplified assumptions, and are for reference only, not a basis for investment decisions.
Tools that work well together

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Averaging-down (Average Price) Calculator
Calculate your new average price after buying more, and how many shares you need to reach a target average price.