是啊

http://www.nolo.com/legal-encyclopedia/employment-at-will-definition-30022.html

Are You an At-Will Employee?

The law generally presumes that you are employed at will unless you can prove otherwise, usually through written documents relating to your employment or oral statements your employer has made.

所以我回答楼主的是，“一般说来”没有问题。但是谁知道楼主签的是什么东西。