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Reproduced for information

Sub-section 2 of Section 2 of Civil Servants Seniority Rules 1993 says:

Seniority on initial appointment. --- (1) Persons initially appointed on the recommendations of the selection authority through an earlier open advertisement shall rank senior to those appointed through a subsequent open advertisement.
(2) If two or more persons are recommended in open advertisement by the selection authority their inter se seniority shall be determined in order of merit assigned by the selection authority.
(3) If only one candidate is recommended in open advertisement by the selection authority, he shall count his seniority form ---
(a) the date of recommendation by the selection authority, if he was already holding in the same post on ad hoc basis; and
(b) the date of his joining the post after being recommended by the selection authority if he was not already holding the same post.