The Medicare Improvements for Patients and Providers Act of 2008 was enacted on July 15, 2008. The Act is retroactive to July 1, 2008 and allows outpatient therapy service providers to submit the KX modifiers on claims that meet the exception criteria for therapy services through December 31, 2009. The limit on incurred therapy expenses is $1810 for Occupational Therapy services per calendar year and $1810 combined for Physical and Speech Therapy services per calendar year. Services billed beyond this limit must meet exception criteria to allow use of the KX modifier.