For Eb-1B, your employer needs to do the following:
a. submit a permanent job offer letter that directly addressed to you;
b. sign the I-140 form.
c. provide documents showing they hire at least three full time
researchers with documented achievements (the researchers’ resumes, job
title, papers published, patents filed or granted, etc.),
d. Provide documents showing they have the ability to pay you the
proffered salary (company’s annual report, audited financial statement, or
if your company hires more than 100 employees, a statement from the chief
financial offer).