Tens of millions of Americans are becoming accidental shareholders.

They own insurance policies or annuities from mutual insurance companies and many of these companies are going public and offering customers some stock.

John Hancock went public at the end of January, making shareholders out of an estimated 1 million of its policyholders. Sun Life of Canada and Metropolitan Life will follow suit in early spring scattering shares on nearly 9 million more.

Policyholders aren’t forced into owning shares. In most cases, you can choose between taking stock and taking an equivalent sum in cash.

Which to choose? Here are some questions, to help you decide:

– Are you an experienced and risk-taking investor? If not, you’re safer with the cash. Put it into a bank account or add it to your diversified mutual fund.

– What are the shares worth? If the payout is small, relative to your other assets, you might shrug your shoulders and take a flyer on the stock. If the payout is large enough to be interesting, you might want to diversify the investment.

– What are the company’s prospects? You’ve probably read that initial public offerings (IPOs) soar in price when they come out. But those are mostly tech stocks and Net stocks.

– Do you have a better use for the money? “Ask yourself if you’d rather own another stock,” says planner Steve Estrin of the Financial Advisory Group in Houston. Or perhaps you could use immediate cash.

– Do taxes matter? If you take cash, you’ll generally pay a long-term capital gains tax in the current year. If you take stock, you’re not taxed on the gain until you sell.