JUDGMENT :

SIDDHARTH MRIDUL, J.

(Via Video Conferencing)

1. The present writ petition under Article 226 and 227 of the Constitution of India has been instituted by Dr. S.N. Sharma, the petitioner herein, assailing the order dated 27.08.2019 passed by the learned Central Administrative Tribunal, Principal Bench, New Delhi, (hereinafter referred to as the ‘learned Tribunal’), dismissing OA No. 463/2016 titled as ‘Dr. S.N. Sharma & Anr. vs. UOI & Ors.’, whereby the petitioner’s plea for setting-aside and quashing the order dated 28.08.2014 issued by the Department of Personnel & Training (hereinafter referred to as the ‘Respondent-3’), and communication dated 10.11.2014 issued by the Ministry of Water Resources, Government of India (hereinafter referred to as the ‘Respondent-1’) addressed to Central Soil & Materials Research Station (for short ‘CSMRS’) (hereinafter referred to as the ‘Respondent-2’), determining the proposal of regularisation of services of Scientist 'B' officers of CSMRS who were promoted on ad-hoc basis, in the negative, and holding that the period of ad-hoc service rendered will not be counted towards eligibility service for promotion to post of higher grade, was reje