Can the social security paid by the company be transferred?

You can turn.

The process of transferring to social security is as follows: When you are employed by Company A, Company A will go through the employment procedures (registration) for you at the local social security center, and pay social security for you according to the national regulations. When you leave Company A, Company A will go to the social security center to handle the resignation formalities for you (stop paying social security). At this time, you are equivalent to an unemployed person. If you don't join other units for three months (you haven't paid social security for three consecutive months), the insurance center will temporarily seal your personal account.

When you are employed by Company B, Company B will go to the Social Security Center to handle the employment registration and social security payment procedures for you according to the above procedures, and so on. No matter how many companies you change, the social security paid by these companies is in one account (your account).

The problem now is that company A agrees not to let you go. If you are not allowed to go, Company A will not go to the social security center to handle the resignation formalities for you. After you enter Company B, Company B can't go through the formalities of paying social security for you, but Company A must continue to pay for you. General enterprises won't do such stupid things (people don't work in the company, but they have to pay social security). At most, they demand compensation from you for breach of contract. Please refer to the labor contract for details.

The above answers are for your reference only.

Further reading: How to buy insurance, which is good, and teach you how to avoid these "pits" of insurance.