41 U.S.C. § 109

1. (a)In this subtitle, the term “major system” means a combination of elements that will function together to produce the capabilities required to fulfill a mission need. These elements may include hardware, equipment, software, or a combination of hardware, equipment, and software, but do not include construction or other improvements to real property.
2. (b)A system is deemed to be a major system if—
   1. (1)the Department of Defense is responsible for the system and the total expenditures for research, development, testing, and evaluation for the system are estimated to exceed $75,000,000 (based on fiscal year 1980 constant dollars) or the eventual total expenditure for procurement exceeds $300,000,000 (based on fiscal year 1980 constant dollars);
   2. (2)a civilian agency is responsible for the system and total expenditures for the system are estimated to exceed the greater of $750,000 (based on fiscal year 1980 constant dollars) or the dollar threshold for a major system established by the agency pursuant to Office of Management and Budget (OMB) Circular A–109, entitled “Major Systems Acquisitions”; or
   3. (3)the head of the agency responsible for the system designates the system a major system.