> Your eye care provider must give you a copy of your contact lens and eyeglass prescriptions — whether or not you ask for them.
http://www.consumer.ftc.gov/articles/0116-prescriptions-eye-...
I received my prescription from the optometrist without asking.
The only thing missing is the pupillary distance measurement. There is not even a place for it on the prescription form I received. I didn't know it was something I'd need until reading this thread and checking out zennioptical.com.
I will be calling them tomorrow to get that.
Some optometrists are a little hesitant to give you your prescription data, but it's yours. When in doubt, ask them up front whether they're willing to give it to you after the exam; if not, walk away.