Under the proposal, anyone who owned such a security would have to mark it to market value at the end of each year and pay taxes on the gain, assuming there was one, at ordinary income tax rates.

Then there is the strategy of “covered call writing,” followed by some cautious investors. An investor who owns, say, 100 shares of I.B.M., sells a call option allowing the purchaser to buy the stock at a fixed price for a certain amount of time. The current law treats the profit or loss on the option as a capital gain or loss, but does not levy any tax on the stock until it is actually sold.

Under the Camp proposal, that would change. When the individual sold the covered call option, that would be treated as being equivalent to the sale of the stock, and capital gains tax would be owed on the difference between the market value at the time and the price the investor paid. While the call option was still open, any gain or loss in the stock would be treated as ordinary income or loss, as would any change in the value of the option.

If that provision became law, covered call writing would probably fade away as a tactic used by individuals, at least when the investor had a gain in the stock before writing the option.

The taxation of bonds bought at a discount on the market would also change. Bonds trade at a discount because their interest rate is below the current market level or because the issuer’s creditworthiness has fallen since the bond was issued.

Right now, “there is a tax benefit to investing in discount bonds as opposed to current-pay bonds with the same yield,” said David C. Garlock, the director of financial services for Ernst & Young’s national tax practice. That is because you do not pay tax on the rise in the bond’s value as it nears maturity, until the bond is sold.

That would change. The unpaid interest would accrue and be taxed each year, just as it is now on zero-coupon bonds. There is a partial exemption for owners of distressed bonds bought at deep discounts, but they would still owe some taxes each year, even if they did not sell the bond.