How to view the progress of Professional Syndicate?

I'm not sure if it's about you being unable to find the place where it's shown or about requirements... anyway,  this will be an answer to both, just to avoid confusion.

Go to Awards in Battlelog and select Assignments from the list. Syndicate assignments are near the bottom (between Class Assignments and Misc). Professional Syndicate is the first assignment from the left in second row among Syndicate Assignments.

If requirements only show question mark, then it means that you didn't complete all the pre-requirements yet. For Professional these are:

• Professional Assignment 2
• 1 Professional Specific Guns And/or Gadgets Purchased
• Unlock Professional Gold Service Star 1