if already vested, the money in tiaacref account is yours, you can leave it there or roll over to other places other than tiaacref (but still in retirment account, not regular cash account)

可以转去rollover ira，没penalty的。vanguard，fidelity这些大fund公司都有

rollover ira是不是也是养老金账户？私人就可以开吗？
还有什么是vested?

是的，就是私人开的。vested在什么上下文中