I used to really love Glassdoor. In theory, the site is awesome!
That is, until companies started figuring out how to work the system. Now, it’s kind of like the TripAdvisor for corporations. You know about 25% of the reviews are total crap.
Here's a couple of easy ways to tell if reviews are genuine or not.
1st: Sort reviews by date. Are there a ton of great reviews in a matter of a week? Maybe even all on the same day? This is called a Glassdoor Campaign & it is usually done by companies that have a less than stellar reputation for employee satisfaction.
2nd: Next to their rating, click on "rating trends" You'll see the spike when this campaign was done, down to the month & year. Look at all of the reviews prior to this campaign and you will get the REAL picture of what it is like to work for this company. If you are going to use Glassdoor to judge a company by it's culture & employee satisfaction, this is the way to get the real window into the organization.