Is there a way to find out how many investors there are for any given stock?

This might help for the NASDAQ.

Haven’t found anything for the NYSE that is similar.

Any competent stock broker should be able to answer that question for you.

I suggest you might wish to check with the Merrill LYNCH MOB.

You won’t ever know that number.
SEC only requires that companies with a 5% or greater ownership be identified along with the buying and selling of executives.
Way too many people own stocks “in trust”. All the stocks I own are that way, therefore, I’d never show up as an owner. I don’t know if the custodial companies even know who actually owns the stocks they have custody of? Could easily be that custodial records are: 100 shares MSFT/Charles Schwabb; and the next source would be Chas Schawb who knows which of their clients own how many of the 100 shares.
SEC site: EDGAR allows you to search ownership (ie 5% + execs)

But a competent stock broker will go out of his/her way to try and get you the information anyway, just because s/he hopes that doing so, will result in a stock transfer to you, that will garner a load for him/her.

As information, they are called “brokers” because, after every transaction through them, you are usually “broker.”

Also, you would never know for any companies that are private rather than public. jvgr gave a great answer.

It seems to me that knowing (unless it is an executive with need to disclose) is a bit of a violation of privacy. You can’t really know what someone has in their bank account. Why should their stock ownership be a matter of public record?

JackAdam: I’m sure that your stockbroker will do their utmost to tell you whatever you want to know if you’re proposing to buy 5% or more of Microsoft or other large company, but I don’t think they would be able to answer that question. What’s the intent of the question? Most only want to know who has the potential to control a company, not to avoid investing in any company that JackAdams has a 100 so shares in.

Marina also brings up a good point.