请问有做contractor的MM吗？签合同要注意什么？

他要我这么多个人信息，感觉很不踏实，是都这样吗？thanks!

A copy or picture of your social security card.
A copy or picture of your ID card
A copy or picture of completed and signed W9 form which is attached
A copy or picture of completed and signed Business Associate agreement which is attached
Signed Independent Contractor form which is attached
A copy or picture of certificates of blow training

第一个第二个都没有要啊，后面几个有的

都要了啊。。

我也都要了！