They almost certainly are. My last drop of the night. I think.....
Hopefully I made some new fans of SS tonight as it's one of my favorite series ever made (TFE, TSE, and number 3, the others are fun little games but don't really count as SS games) and if you haven't figured it out by now anybody who grabbed some codes these are all from the current Humble weekly sale, think about supporting them if you can, sure as hell can't beat the price.
Serious Sam HD: The First Encounter
AE733-YJP8Q-YMBVJ
Serious Sam HD: The Second Encounter
P2HW6-ZMRFI-80DXA
Serious Sam Double D
XX7CI-44I32-KF4P5
Serious Sam: The Random Encounter
ZDGZ8-6A536-JXCR9