How does FHA define owner occupant?

At least one borrower must occupy the property as their principal residence within 60 Days of signing the security instrument and intend to continue occupancy for at least one year.

For additional information see Handbook 4000.1 II.A.1.b.iii.(A)(2)(a) available at http://portal.hud.gov/hudportal/HUD?src=/program_offices/administration/hudclips/handbooks/hsgh