** Shares of U.S. oil refiner Phillips 66 PSX.N rise 4.3% to $129 premarket
** Elliott Investment Management has built over $2.5 bln stake in co and plans to push for operational changes to boost its stock, a person familiar with the matter told Reuters
** Elliott to push Phillips 66 to sell or spin off its midstream business - source
** Elliott plans to seek a number of changes to simplify PSX - WSJ
** Last week, Honeywell split up into three independently listed cos after Elliott took a $5 bln stake
** PSX lost 14.5% in 2024, and is up 8.6% YTD
(Reporting by Pranav Kashyap in Bangalore)
((Pranav.Kashyap@thomsonreuters.com; +919886482111;))