I have worked on a lot of cases regarding the Shareholders’ List for corporations (주식회사) and for limited liability companies (유한회사). This is a very important and sensitive issue, and one with which most expats are not familiar with at all in Korea.
When forming a corporation (주식회사), if you plan to possess more than 50% of the shares, you may have the liability of paying tax if your company falls into bankruptcy. If this is you, you are known as the "major shareholder;" if however you own less than 50%, you don’t have any tax liability at all.
In my research I've found a lot of major shareholders of Korean companies split their shares with their spouse or even with their employees in an attempt to show ownership of less than 50% of the company. Be warned, however, that the Korean government is not particularly stupid, and it assumes that shares owned by a relative or spouse to be actually owned by the major shareholder.
When transferring shares, you should also be intimately aware of your company's Articles of Incorporation (정관) and check any restrictive conditions for share transfer, since some limited liability companies may not allow those share transfers without previous approval via a general shareholders’ meeting or perhaps even without all shareholders’ consent.
When you do finally transfer shares in your company, you will need to pay the government a “share transaction tax” of 0.5% of the transaction price. Thus, if the value of the transfer is one million won, you will need to pay a 5,000 won tax in the case of an unlisted small- or medium-sized company.
You will also need to pay taxes on any gains from the share transfer (the difference between the purchase price and the selling price). You must carefully check the purchase contract you signed and pay any gains when filing, otherwise it could be considered tax evasion by the tax office. It's also true that if you transfer shares at less than face value for some reason, and then later transfer them again at the face value, you will then need to pay capital gains taxes from the share transfer.
To minimize any tax risk for share transfers, you will need to carefully evaluate the price of the shares with your accountant lest you expose yourself to some very expensive tax liability. Making a proper contract is also vital, since without it you could have some big problems down the road. For instance, how can you insist that you’re one of the company's shareholders in the near future if you failed to see your name on the shareholders’ list at the end of year? You need a clear contract with the inclusion of the registered seal certificate (인감증명서) of the seller for your file; if you don't have this, it can be very difficult trying to convince a judge that you are actually a shareholder.
When everything is ready, you need to ask the company to register the buyer's name on the shareholders’ list. Once the buyer can see their name on the registered shareholders’ list which has been filed at the tax office, along with the buyer's ARC number, the job is done.
The legal filing date for a share transfer is a bit different from a property sales case: if it is sold within the first quarter, you need to file within two months from the end of the that quarter. For example if the shares were sold Feb. 25, you would need to file it by the end of May. Remember too, that the liability for paying the taxes due on the share transaction and gain falls on the seller, not the buyer.