As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CABIN ODOR: RIGHT AFTER TAKEOFF FROM KBVU WE HAD A STRONG UNUSUAL ODOR IN THE COCKPIT AND CABIN. IT SMELLED MORE LIKE AN ACM ODOR THAN AN ELECTRICAL ODOR. I WALKED TO THE BACK OF THE PLANE TO LOOK FOR SMOKE/ODORS. THE ODOR REMAINED BUT I COULD NOT FIND ANY VISIBLE ISSUES. WE DIVERTED BACK TO LAS AFTER SPEAKING WITH THE FODM. CORRECTIVE ACTION: REPLACED HEPA FILTER. OPS CHECK GOOD. IAW CE680A AMM 21-70-10.