Fog Creek has(had) 3 major products:
- FogBugz: profitable but less of a success than Atlassian
- Trello: not profitable (sold to Atlassian)
- Stackoverflow/StackExchange : not profitable yet 
According to the open-office "distractions/interuptions" theory of killing productivity, the Atlassian programmers should have been severely handicapped and as a result JIRA should have evolved at a snails pace. Instead, the opposite happened and Atlassian JIRA released more features than FogBugz. Both FogBugz and Trello lost to Atlassian.
That Joel Spolsky post about private offices gets repeatedly cited in threads about its benefits but I recommend people not mention it. It undermines their point. It's ineffective at convincing executives. However, it's very effective at making other programmers reading it nod in agreement (aka "preaching to the choir").
Don't link ineffective articles devoid of business evidence that happens to confirm your desires. Instead, study the way some executives actually think. Too many programmers dismiss companies' rationale for open offices merely as "saves square footage costs" or "it's a way to spy on employees because of distrust". Yes, some of that may be true but others also have different reasons. (Take a look at the Mark Zuckerberg video I linked and listen to what he's saying about his desk in the open floor plan. Is he trying to recreate that elbow-to-elbow collaboration he had at the Harvard kitchen table or is he just trying to spy on people? Would that Joel Spolsky article convince Mark Z to build private offices? No? Why not?)