On further inspection of this, it seems like there are quite varied reports. While corestandards.org (obviously biased) stated:

"Yes, teachers have been a critical voice in the development of the standards. The Common Core drafting process relied on teachers and standards experts from across the country. The National Education Association (NEA), American Federation of Teachers (AFT), National Council of Teachers of Mathematics (NCTM), and National Council of Teachers of English (NCTE), among other organizations, were instrumental in bringing together teachers to provide specific, constructive feedback on the standards."

That seems very vague. What I learned was that governors and selected groups of teachers worked together on this - however, this following article directly refutes that claim. (Sorry, am not good at formatting)

http://blogs.edweek.org/teachers/living-in-dialogue/2013/12/the_making_of_common_core_crea.html

"The essence of the Common Core was developed by a handful of corporations and corporate-funded think tanks who wanted schools to meet certain benchmarks to better prepare the employees of the future. Common Core defenders cannot change that reality by pretending that the first step in a development process is a review, or by repeatedly calling it a "fact" that teachers were involved in writing the standards."

So while they did genuinely bring in teachers, whether their role was of actual importance is disputed. Thanks for bringing this up - it definitely warrants some more thought and investigation. Some teachers in the "review" process felt like they had an impact, and others did not.

Thank you for bringing this up - it is definitely making me reconsider some of my inital thoughts about CC.