In reference to the patent: US9474214
The best way to determine the expiration date of a US patent is at the US Public Pair site. Go to Pair, get past the CAPTCHA and then select "Patent Number" and enter 9474214. Pair is extremely picky about format so don't add any commas. From there you can find that this patent will expire 20 years from it's filing or 371(c) date of 09-07-2012 plus 523 days of patent term adjustment. If I calculate correctly that ends up with an expiration date of February 12, 2034.