There are various visa options for entrepreneurs both inside and outside the USA, between non-immigrant and immigrant visas. Non-immigrant options include B-1 for temporary business visits, the International Entrepreneur Rule for temporary parole, and treaty visas like E-1 and E-2. Immigrant visa options include EB-1 for exceptionally qualified individuals, EB-2 National Interest Waiver (NIW) for those impacting US interests, and EB-5 for investors. Overall, EB-2 NIW offers flexibility in job changes within the same field and may lead to a green card without being tied to a specific job or employer.

Owning more than 50% of a company makes obtaining an H-1B visa difficult under current regulations. This is because the H-1B is for employees receiving a base salary, and owning a majority share raises doubts about a genuine employer-employee relationship. While regulations easing this restriction are pending, they haven't been finalized yet.

However, if you're a minority partner with your brother holding the majority and the job aligns with your field, securing an H-1B (concurrent or full-time) may be possible. Unfortunately, getting a green card through this company wouldn't be feasible due to your ownership. Consider exploring the EB-1A green card category, which recognizes individuals with exceptional ability in their field and doesn't require employer sponsorship.

Being turned away at a US airport or port of entry can have significant consequences. Here's what you need to know:
Voluntary Withdrawal: If you choose to withdraw your application for admission, you avoid a 5-year entry ban but may have limited options when seeking to re-enter the US in the future.
Refusal of Admission: This comes with a 5-year ban on re-entry. In some cases, you may be able to apply for a waiver.
Fraudulent Employers: Involvement with any employer who engages in fraudulent activities can lead to a permanent ban on entering the US. It's incredibly difficult to get a waiver in these circumstances.

To avoid these situations:
Be Aware: Stay informed about potentially fraudulent employers. Universities may alert you if they suspect issues.
Consult an Attorney: If you've worked for an employer you now believe to be fraudulent, immediately consult an immigration lawyer. Your level of involvement and when you leave the employer will have a significant impact on your potential liability.
Important Note: There are currently no known successful lawsuits against fraudulent employers in these types of situations.