CBS News Correspondent Jim Axelrod reports her request was turned down at a shareholders' meeting on Wednesday.
Sister Pat Daly, who represents a clergy-based pension fund with a $15 million stake in ExxonMobil, says the energy giant has isolated itself from the other big oil companies with a dinosaur attitude on global warming.
If there's a growing consensus that greenhouse gases are raising global temperatures, Daly and her fellow protesters say executives at ExxonMobil are not about to embrace it.
Daly says, "They're saying there's not enough science. They will tell you, 'We're concerned about global warming.' But they're not going to admit that it's actually happening."
Other oil giants like Shell and BP Amoco have pledged to reduce their greenhouse gas emissions to 10 percent below their 1990 levels.
DuPont Chemicals has gone even further, promising a 65 percent reduction.
ExxonMobil, on the other hand, has no such targets.
ExxonMobil insists until the evidence conclusively links carbon emissions to global warming, there's no reason to change the way it does business.
Their CEO Lee Raymond says, "We're going to follow the science, we're not going to follow what's politically correct."
Mike McElroy, Harvard's chair of environmental studies, says, "In terms of honest assessment of the science, yes, this is a serious problem, time to act Exxon is leaning to the side of inaction."
He says, "They simply leave the public with the view that 'Gee -- we don't know enough to do anything.'"
ExxonMobile Vice President Frank Sprow disagrees, saying: "This is complicated. Don't believe statements that say it's clear that things are warming. It's not clear."
The company has taken this idea to the public in a series of ads, saying views on warming are "just as changeable as your local weather forecast."
When asked if ExxonMobil's assessment of the credibility of the threat of global warming has evolved, Sprow replied, "I'd say that's unchanged over the last several years."
Wednesday's attempts to change the company's views on global warming during the shareholders' meeting were turned back, leaving dozens of critics with little to do but shout in frustration -- outside the meeting.