The Ministry had on February 23 suspended Shankar following allegations of irregularities in a tender for buying 21 Blowout Preventers (BOP). However, a chargesheet against him could not be filed within the stipulated 90 days.
"Pending completion of the inquiry, he is being reinstated to his position," a top source said.
ALSO READ: ONGC not liable to pay sub-contractors
Shankar, 54, is the youngest director on the board of the nation's most profitable oil company. He was appointed Director (Technology and Field Services) on December 1, 2012.
The source said, the Supreme Court had in February held that a government employee's suspension order would not stand beyond 90 days unless the prosecution files a chargesheet within that period.
The court had also stated that even if a memo of charges is filed within 90 days, suspension can only be extended by a reasoned order.
In case of Shankar, who was suspended following allegations of irregularities in a BOP tender when he was General Manager (Drilling), no chargesheet has so far been filed even after more than four months.
The tender, which was originally floated in 2008, has not been awarded yet, purportedly due to issues regarding technical competence of the lowest offer. Also, there was a representation from one MP, who is now a minister in the NDA government, against the lowest bidder.