A Texas jury upheld the claim and awarded Pennzoil $10.53 billion in damages.
Texas juries must choose either a life sentence, with possible parole after 40 years, or the death penalty.
After telling their side of the story to a Texas jury, Bunker and Herbert were acquitted.
Robert Tennard was convicted of capital murder by a Texas jury.
Witnesses who appear before Texas grand juries are forbidden to discuss their testimony.
Texas juries in capital cases must make a prediction.
One notable lawsuit occurred when a Texas jury awarded $32 million (later reduced to $4 million).
The same Texas jury determined, in the sentencing phase of the trial, whether Barefoot should receive the death penalty.
Last August, a Texas jury awarded a man $253.5 million, though state law will automatically reduce that award to $26.1 million.
But legal scholars say the most intractable issue involves unusual instructions that were given to Texas juries from 1989 to 1991.