I work in software in a large office at the moment, we have hundreds of employees but only a hand full of females (and mostly in administration). In my last job it was roughly 50% females, same industry but significantly different make up. The only visible difference is that in my current job all the management are males in my previous job one of the founders (but not CEO) was female.
So the information that has not been provided, is how many females want to work for your former company, versus how many males?
If more females want to work there but couldn't, then there is an issue with someone preventing equality-of-opportunity for those females.
However it could be that your current work are the ones with the problem. What if far less females want to work in that industry than males? Then someone at the top is preventing equality-of-opportunity again, for the males this time.
You cannot know which company is right without getting the right data on preferences.
It's very tough, I don't know the solution, but I know that focussing on enforcing what we perceive to be correct outcomes will not work.
Obviously I'm not recording statistics on everyone that applies for a job, but it's the same industry and the contrast is stark. What I can say is that pretty much all the females in this office are young and attractive. My previous work place had more of a variety of appearances. I also run a large meetup group in Wellington for people in this industry and the people who struggle the most to find jobs always seem to be overweight and older females.