Hey guys,

 Is this legal to run a cart business in mall in opt. heard that opt holder can start the business during opt , is this right?

This is hilarious man. Just read basic OPT guidelines before asking here in sajha.

As for your question, here are the answers;

Why don't you "manage business" of a chinese buffet by working as a waiter if you are "business major"
or program their billing computer if you are "software engineer"
or inspect food hygiene, if you majored in food science or even toxicology
or maintain heating and cooling systems - engineer
or...whatever

A cart business is something like things stated above. However, you DEFINITELY can start a business during OPT, not a cart business. I can understand how hard to find a job, but please don't waste your time in such crazy ideas. Good luck!

Wow, OPT holders can start business? Nice, I didn't know that. And how can the green card process continue? How to change the F-1 status to permanent residence status after opening a business? Thank you in advance.

Self-employed business owner:
Students may start a business and be self-employed. In this situation, the student must work full-time (at least 40 hours/week). The student must be able to prove that he or she has the proper business licenses and is actively engaged in a business related to the student’s degree program.

Mr. Santoshgiri posted this information a while back:

Please also consider the following viewpoint of  attorneys, emphasizing that although self employed business owner provision exists, the 'Training' purpose of OPT 'without a supervisor' in self employed business and 'future continuance of the business' when the OPT ceases, makes it a shady area:
(Source: Mr. Santoshgiri's posting on Sajha)