The O-1 is a nonimmigrant visa for individuals with exceptional skill in the sciences, arts, education, business, or athletics, or who have a proven record of excellent performance in the motion picture or television sector. The O-1 visa petition must be submitted by a U.S employer or U.S agent, because it is not available for self-petition. The visa holder can stay in the U.S as long as he/she performs in the same activity. 

Period of stay

O-1 visa holders can initially stay in the U.S for up to three years to complete the event or activity. The status can be extended for a maximum of one year at a time. There is no limit to the number of times the O-1 status may be extended. Another good side of the O-1 visa is that there is no annual limit for the number of applications. 

The O classification is designed for the people who are heading to the United States to perform services in connection with an event or series of events. The phrase "event" includes activities such as a scientific project or conference; a lecture series; a tour; a business project or academic session; or an engagement. A job without a particular engagement or project may also fit under this definition if it involves the applicant’s activity. Short vacations, promotional appearances, and event-related stopovers are examples of such activities, but speculative employment or freelancing are not allowed.

The classifications of O nonimmigrant visa are listed below:

• O-1A refers to the people with extraordinary ability in the sciences, education, business, or athletics (not including the arts, motion pictures, or television industry);

• O-1B refers to the people with extraordinary talent in the arts or exceptional achievement in the motion picture or television industries;

• O-2 visa is obtained by individuals who will accompany an O-1 artist or athlete to help with an event or performance;

O-3 visa is for the spouse and children of O-1 and O-2 visa holders.

Requirements

O-1 visa applicants must demonstrate that he/she has an extraordinary ability and is coming to the U.S to work in the area of extraordinary ability.  

In order to be eligible for O-1A classification of O-1 visa the applicants must have expertise and recognized awards in the science, education, business, or athletics which are among the small percentage of people who have risen to the top of that field.  It can be a one time achievement (e.g Nobel Prize) or the applicant has to demonstrate at least 3 of the following proofs:

• Evidence demonstrating the applicant’s confirmation of nationally or internationally recognized prizes or awards for achievements in the field; 
• Evidence of the applicant’s  membership in associations in the field which require exceptional achievements of their members, as judged by recognized national or international experts in their disciplines or fields; 
• Published material about the applicant in professional or major trade publications or major media relating to his/her work in the field, including the title, date, and author of such published material, as well as any necessary translation; 
• Evidence of the applicant’s participation on a panel or as an individual judge of the work of others in the same or a related field; 
• Evidence of the applicant’s significant scientific, academic, or business-related contribution to the field;
• Proof of the applicant’s authorship of academic articles in the field, published journals, or other mainstream media; 
• Proof that the applicant has worked in an essential capacity for prestigious organizations; 
• Proof that the applicant has or will command a high salary or other remuneration for services.