Section 534.502 - Coverage(a) This subpart implements 5 U.S.C. 5376 and applies to-(1) Senior-level (SL) positions classified above GS-15 pursuant to 5 U.S.C. 5108 ; and(2) Scientific or professional (ST) positions established under 5 U.S.C. 3104 .(b) This subpart does not apply to-(1) Senior Executive Service positions established under 5 U.S.C. 3132 , unless the incumbent of the position declined to convert to the SES and, under § 317.303 of this chapter, remained at grade GS-16, 17, or 18 (now the SL pay system) or under the ST pay system;(2) Positions in the Federal Bureau of Investigation and Drug Enforcement Administration Senior Executive Service, Defense Intelligence Executive Service, or Senior Cryptologic Executive Service; or(3) Positions for which pay is fixed by administrative action and is limited to level IV of the Executive Schedule under 5 U.S.C. 5373 .