An Ecuadoran court Tuesday upheld a ruling that US oil giant Chevron was liable for environmental damage in its Amazon basin region by sister company Texaco, but ordered it to pay a reduced $9.51 billion. The Supreme Court upheld a 2012 ruling against Texaco, which operated in the South American nation from 1964-1990, but dramatically reduced the amount to be paid in damages to $9.51 billion from $19 billion, the ruling said.