** Shares of ONGC ONGC.NS and Oil India OILI.NS jump 3.9% and 5.6%, respectively
** CLSA says the government's move to cut royalties on crude oil and gas production is a "big positive" for upstream firms
** Says the surprise cut could lift fair value for ONGC by 7%-9% and for Oil India by 9%-11%
** "This surprise action to cut upstream tax instead of raising it should put fears of new windfall tax to rest," CLSA says
** CLSA estimates the changes imply a blended royalty cut of about 3 percentage points for ONGC; at $80/bbl oil, this could add roughly 20 rupees–24 rupees per share to fair value
** For OILI, the all-onshore production profile means a sharper impact, with potential fair value gains of 9%-11%, CLSA says
** Adds the policy shift signals the government's intent to support upstream investment and production, reducing fears of higher taxation
** Brokerage reiterates its "high-conviction outperform" rating on ONGC
** YTD, ONGC stock jumps ~22%, OILI up ~14%; energy index .NIFTYENR gains 13%
(Reporting by Kashish Tandon in Bengaluru)
((Kashish.tandon@thomsonreuters.com))