If I sold some shares through my stock broker, is there a way to find out who bought the shares I sold? Or is the transaction anonymous, where the buyer(s) and seller(s) will not be able to know the identity of the party they are trading with? I am mostly asking this out of curiosity, to understand if and how stock transactions are anonymous.
Since you didn’t specify a jurisdiction/market, I will use mine:
For U.S. exchanges, the Depository Trust and Clearing Corporation is the seller for every buyer and the buyer for every seller. So, tautologically, the DTCC bought the shares you sold.
Also, the DTCC exchanges shares on behalf of brokers, so even if you pierced that veil it would say that Vanguard, or Charles Schwab, or Robinhood, purchased your shares. It’s bookkeeping all the way down.
Your question reminds me of a quote from IRS pub 550 I recently stumbled across:
You cannot deduct your loss on the sale of stock through your broker if, under a prearranged plan, a related party buys the same stock you had owned. This does not apply to a trade between related parties through an exchange that is purely coincidental and is not prearranged.
To me that quote tells me that most people never know who buys the shares they sell.
I also can't understand what advantage providing this information would give to the people involved in these transactions. The previous owner of the shares doesn't need to provide the tax id number of the person who bought them. All the tracking required is done by the brokers.
Today with High-frequency trading, Day traders, and the ability to purchase fractions of a share, tracking is even more difficult. The bunch of shares you sold could have traded hands multiple times, and been subdivided between multiple investors by the end of the day.
In addition most shares are held in the “street name” of the broker, rather than under the name of any particular investor. So even if your broker provided this service for you it would fail the moment the shares went to a competing broker.
In the past there were actual physical share certificates that stock owners held. So many people still have that idea of what modern "holding stock" in a company means.
It's analogous to paper currency vs. deposits in a bank account. Let's say you have $10000 in a bank account. No bank has a stack of $100 bills that is your deposit. You account balance is nothing but a number in their computer system. If you make a deposit or pay a bill, that number changes up or down as needed so that it reflects your current deposit balance. The amount of "money" in circulation has nothing to do with the amount of paper currency available. In fact there is far more money than there is currency.
Stock trading today works exactly the same way. There are no stock certificates (granted you can sometimes get these at a fairly significant cost plus there are still some people who have long-term stock holdings in paper certificates from long ago) there are just account balances at your broker. There is no way to identify your stock vs. my stock other than a number in their computer that says you own 100 shares and I own 50 shares of MSFT or whatever company we're talking about. When you sell the balance decreases and someone else's account balance increases. But there is no "trail of ownership" that says this individual share was owned by A and then B and then C, etc... That information is not kept nor is it important. All you need to know is that on such an such a date you sold some number of shares and they are now gone and you received some cash into your cash holdings as a result.
Generally you can't tell. Your instruction goes to the broker, the broker transacts with one or more counterparties to complete the sale. The broker might know the counterparty's participant (other brokers) but not the individuals. From memory, in AU at least, the counterparty participant (not the account) is only available 4 weeks later if you pay for the information feed. Ultimately, again in AU, even the brokers have the clearing house to contend with and it's all netted out anyway so in theory even on a busy day it's possible no stock movement occurs between participants.
There are some edge cases where your buyer can be inferred.
- A change of significant interest may trigger a market notice. If that acquisition reflects exactly your sale quantity it might be your buyer.
- A broker might report a cross (in-house trade) to the exchange so they would know the counterparty. I don't think they'd share that with you though.
- In the above cases, you might buy & sell with your own accounts (though you'd do a transfer in reality).
- There is an aggressive on-market takeover or buyback which you can pretty much guess who's buying at almost any reasonable price.
But basically, no, you can't know who bought your shares or, conversely, who you bought them from.
The information is not just unknown, but in large parts unknowable:
Your shares are not necessarily the only ones traded at a trade - there are often dozens of traders participating in a single transaction, all selling or buying at the same price at the same moment. You cannot define clearly who got whom’s shares.
Though another answer emphasizes the lack of share certificates in modern trading, think of it a bit like this system for trading tickets:
Suppose Disney World is having a special event at Magic Kingdom on a particular future date. It offers a fixed number of tickets (representing the park capacity) for general admission to the theme park that day and those are the ONLY tickets that will be honored for admission that day. Each ticket is exactly as good as any other. These quickly sell out but Disney allows resale of the tickets without any issue.
The Disney store in Times Square has a special room set up with one employee and a big table and a numeric display outside of it. People who have these tickets and want to sell them can take the tickets there. People who want to buy these tickets show up with cash. When a specific person buys a ticket, it doesn't matter which one the employee pulls off the table and gives them, because each one is equally fungible.
Joe brings in 2 tickets and says "I want at least $200 for each ticket" and the clerk notes that down, separately from the jumbled pile of tickets. Mary comes and does the same. Alice and Bob each bring four tickets, noting they want $225 each. Greg brings in one, seeking $1000. The clerk keeps track of how many tickets are available at which price, so after these folks the list says SELL: $200: 4; $225: 8; $1000: 1. The sign outside says 'ASKING: $200'.
Sam comes in and wants to buy one ticket, but is only willing to pay $150, so the clerk notes BUY: $150: 1; and takes note of Sam's information. If another seller in the future came in willing to sell at that price or below, the clerk would call Sam. The sign outside gets a new line which says 'BIDDING: $150'.
Charlie arrives and wants to buy one ticket, at whatever the best asking price is, currently $200. The clerk matches that against the SELL book, pulling a ticket out of the big stack for Charlie and handing it over in exchange for $200 cash. Then the book is updated to say SELL: $200: 3; $225: 8; $1000: 1. Was that Joe's ticket or Mary's, or even Alice's or Bob's? Who knows? It doesn't matter. Joe will get the money since he was first in to the book at that price, but the ticket itself could've been from anybody. The sign outside the door shows a new line, 'LAST TRADE: $200'.
Then, Doug arrives looking for a family four-pack, again at the best offer price. The clerk consults the book and asks for $825, gets that in cash, and hands over four tickets; the 'LAST' and 'ASKING' lines on the sign change to $225. Ed comes in asking for 10 tickets at a price of $225 or better; buying up all the remaining available tickets ('ASKING' goes to $1000) and adding to the order book on the buy side, filled later when another seller comes in - more likely, now that the door sign says 'BIDDING: $225'. In each of those cases, the clerk is matching one incoming order against multiple book orders. None of the buyers or sellers knows or cares who or how many people are on the other side of that order, just the dollar amount and the quantity. Real stock exchanges are like this, but with a LOT more parties involved. The clerk doesn't even have to keep track of how orders were matched as long as all parties get the funds (or returned tickets if a seller's orders aren't matched) due to them. There are a few wrinkles around audits and price improvement rules, but they aren't really needed in this simplified analogy.
Does that help?
I feel a lot of the answers here miss the mark. There are several aspects at place here.
Market data feeds will report trades. The reported trades will contain information about the orders that were involved in that trade. From those orders, you can tell who the brokers were who were involved. So you will have your broker on one side, and on the other side, the other involved broker.
So yes, on a fundamental level, you can see what broker purchased your shares. That's generally as about as much information as you're going to get.
There are answers here that say that because there are lots of orders and trades, it becomes impossible to track. This is incorrect. You just need the appropriate market data feed and an ability to filter by your order number.
A separate question is, can you track ownership of "your" share beyond that?
The answer is generally not, because shares are fungible.