The answer: There is NO central certifying body in Six Sigma.
There is no standard certification body, and different certification services are offered by various quality associations and other providers against a fee (Coryea & Cordy 2006, p. 65)
It is the Master Black Belt that certifies an individual, only "through" the organization that he/she represents. Organization may be an educational institution (like iAcademy School of Continuing Education, Boston University, Arizona State University, etc.), consulting firms (like Six Sigma Philippines, Juran Institute, Motorola Solutions, etc.), professional associations (like American Society for Quality, Institute of Industrial Engineers, etc.), and a company's internal certification (like GE, Motorola, American Express, etc.).
It is the Master Black Belt that certifies an individual, and NOT the organization. If an organization loses its Master Black Belt, it also loses its capability to certify an individual.
Now, for the risks of having no sole certifying body would be, one, fly-by-night six sigma training institutions or certification mills; two, once you get certified, it means you are only as good as the person that awarded you your certification.
There are three institutions proclaiming, directly or indirectly, that they are the "central" certifying body of Six Sigma. What's funny is, not in any point in time Motorola, GE, and ASQ have proclaimed that they were the "central" certifying body of Six Sigma, then out of nowhere three decades later, these 3 companies directly or indirectly started proclaiming, that they are (or will be) the "central" certifying body of Six Sigma:
A number of my Six Sigma certified friends in the Philippines will get mad at me because they paid IASSC to make them part of the 'accredited' training associate and training organization.
IASSC is saying that it is the only independent third-party certification in the Lean Six Sigma industry. It means, it only certifies persons and institutions, and according to IASSC, it removes the conflict of interest of being the trainer and then later issuing the certification to the student.
The problem here is, IASSC is advocating persons who want to get certified in Six Sigma to take the training from the list of its "accredited" training institutions/ persons. The "accredited" training institutions/ persons pay IASSC 700 USD each year, to be on its list. Isn't that another conflict of interest? Is IASSC a testing/accrediting firm or a marketing company?
Furthermore, it will even become more expensive to get certified in Six Sigma since students have to pay an examination fee to IASSC to take a pen-and-paper or online exam (195 USD for Yellow Belt; 295 USD for Green Belt; 395 USD for Black Belt) to get evaluated.
There is nothing new to IASSC's Body of Knowledge (BOK). Topics are similar to Motorola and GE's Six Sigma curriculum, like what most Six Sigma Master Black Belts worldwide are using.
The Council for Six Sigma Certification is saying that it is the Official Industry Standard for Six Sigma Accreditation.
Like IASSC, its website does not state the name of its officers, consultants, institutions, Six Sigma expert-members that form the "Council."
It doesn't even publish its office address which is another red flag.
Also, the rates one needs to pay to get accredited are not published on the website.
While the 3 part process to be accredited are logical and indeed a best practice, there is really nothing new to its body of knowledge (BOK).
The beauty of Six Sigma is it is very flexible. A company can customize its Lean Six Sigma initiative on how it sees it fit to the organization. As long as the methodology and tools are used properly, and there are results, there is no need for a one size fits all body of knowledge.
While I am a big fan of ISO 9001, the International Organization for Standardization or ISO, launched ISO 13053:2011 and named it "Six Sigma". The technical committee, ISO/TC 69, developed this new standard composed of 2 parts: Part 1 is about the DMAIC methodology, and part 2 about Six Sigma tools and techniques.
If you ask me what's new, there's none. And true enough, 4 years have passed, and no one bought the standard and the idea. ISO attempted to be the "central" certifying body, perhaps to get a piece of the Six Sigma market which is still growing, even it is almost 30 years old.
The declining number of companies using ISO standards might have caused the technical committee to repackaged Six Sigma and sell it like it is something new.
Coryea, L. & Cordy, C., 2006. Champion's Practical Six Sigma Summary. Xlibris Corporation.