
To register a .pro you have to be;
The key requirement is 2). If you are licensed by a government certification body or a government approved authority, you are likely to meet 1) and 3). It's difficult to see how you could be in bad standing with a licensing authority but still be licensed. If you were retired, you could possibly meet 2) and 3), but not 1). In a nutshell, you need a license number and the issuer must be government approved.
The licensing requirements throw up some noteworthy inclusions and exclusions. For example, Ian Fleming's fictional character James Bond would presumably be eligible to register a .pro because he provides professional counter-intelligence services, he's licensed to kill, M16 is a government approved authority, and he has the world's most famous license number, 007.
In contrast, as an individual, Bill Gates, would not meet the .pro eligibility requirements. He scored 1,590 out of 1,600 on his SATs giving him an estimated IQ of 170, has 5 honorary doctorates, but dropped out of Harvard in 1975 to work on Microsoft BASIC with Paul Allen at Micro Instrumentation and Telemetry Systems (MITS).

As well are restrictions on who can register a .pro, .pro registrants must abide by a terms of use agreement. This states that you shall not;
One of the most common questions potential .pro registrants have is how to meet the .pro licensing requirements if you are not a conventional paper qualified professional. There are two options to consider, please check with RegistryPro first before relying on either;
The .pro restrictions in place until 8 September 2008 were extraordinary and worth mentioning in the context of how not to go about developing a domain extension. Originally, only accountants, lawyers, engineers, and doctors in Germany, Canada, the UK and US were permitted to register.
Registrants could either register a profession specific third level .pro, for example JohnSmith.law.pro; a redirecting second level .pro, for example you could register JohnSmith.pro but visitors would get redirected automatically to JohnSmith.law.pro; or if certain additional criteria were met, a resolving second level .pro, for example JohnSmith.pro, that resolved as JohnSmith.pro rather than redirecting to JohnSmith.law.pro.
The criteria for registering a second level resolving .pro were that you had to have two profession specific third level .pros, for example, JohnSmith.eng.pro and JohnSmith.law.pro. That meant only companies with two or more professionals providing two or more professional services, legal and engineering in our example, could register a second level resolving domain.
Unsurprisingly, by February 2005, 9 months after launch, there were just 1,296 .pros registered. On 2 March 2005, Encirca launched its Pro Forwarding service. This took advantage of two omissions in the .pro registry management contract;
Encirca registered two profession specific third level .pros and leased out second level .pros to unverified registrants. Encirca was the legal owner and lessee was the beneficial owner. The reg fee was $99 per year mixed in with occasional $49 and $75 promotions. Total .pros registered rose to around 6,500 with Encirca taking about 80% of the market.
The restrictions on .pro are unnecessary, anti-competitive, discriminatory, and have stifled the growth of .pro for 5 years.
.pro licensing requirements exclude entrepreneurs and creative professionals who are qualified by experience. These people drive business online and without their input, .pro will continue to fail. Paper qualified professionals do not have the technical skills or the risk appetite to develop .pro.