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Trading Calculators
Calculate how much your ownership and the share price are diluted when a rights offering or CB conversion occurs.
Allotted shares = my holdings × (new shares / existing shares). In practice, it may be slightly lower because of the employee stock ownership allotment and similar.
Enter your values and press Calculate
Share count dilution
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Theoretical price (ex-rights)
Change in my ownership
Change in my holding value
Dilution risk
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 existing total shares outstanding, new (conversion) shares and issue (conversion) price from the DART filing (DART, the FSS electronic disclosure system).
Enter your share count to see the change in ownership and value.
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 issuer's disclosures (DART).
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.
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.
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.
Last updated: November 2, 2026
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