I have H1B Approved until 2018 but not travelled to USA. Can I go for B1 stamping?

As I already got 3 years stamping for H1B, can I go for B1 stamping now?

If yes - is my H1B Visa gets cancelled?

Do I need to transfer H1B Visa to current company before I apply for B1 Visa?

Can I transfer H1B Visa without even visiting to USA to new Company?

Can I hold both H1B / B1 Visas together? (but different companies)

Please help me to clarify these doubts

You can appear for B-1 stamping. There is a possibility that they will cancel H-1B visa stamp while approving B-1 visa.

Canceling H-1B visa stamp doesn’t impact your already approved petition. In future, you can use that petition and re-appear for H-1B stamping.

Having said that, it is also possible they don’t touch the H-1B stamp at all.