Shareholder proposals urging Exxon Mobile Corp. (XOM) - Get Report , Occidental Petroleum Corp. (OXY) - Get Report and PPL Corp. (PPL) - Get Report to produce reports on the impact of climate risks on their long-term strategy were approved by a majority of investors this year -- a major success for investors seeking to push companies to think about environmental issues.

The proposals were nonbinding, which means the energy giants are not obligated to implement any changes in response to shareholder support. Nevertheless, the strong backing could embarrass them into producing a detailed report or taking other actions.

And State Street Global Advisors (STT) - Get Report , one the largest U.S. index funds with $2.6 trillion in assets, has become a key contributor to the success of the measures.

Rakhi Kumar, managing director and chief of State Street's environmental, social and governance investments and asset stewardship program, told The Deal that the index fund backed all three shareholder proposals as well as several other environmental-themed measures that also did well in 2017.

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"We need to understand how sustainability impacts on equity -- how that is impacting long-term strategy," Kumar said.

The proposal at ExxonMobil received the backing of 62% of the vote and was considered a "watershed" moment because of the huge showing of support. The measure asked Exxon to report on the implications of different climate scenarios including one that takes into account a climate agreement reached in Paris in 2015 that seeks to restrict greenhouse gas emissions in a way that limits increases in atmospheric temperatures to no more than 2 degrees Celsius.

President Donald Trump announced in June that the U.S. will withdraw from the Paris accord. Despite the move, measures focusing on climate change did well in 2017 -- similar shareholder proposals focusing on the 2 degrees Celsius level at 10 other companies received 35% to 50% of the vote, a huge vote of support. "Investors have become really focused on climate change proposals this year," she said.

State Street owns about 5% of Exxon shares, making it the oil giant's second-largest investor. So far, Exxon has not responded to the shareholder measure. "It is typical for companies to evaluate and assess how to respond in the fall, so we will be looking for a response," Kumar said.

The index fund recently conducted an in-depth review of 50 reports issued by companies on global sustainability issues and produced a paper outlining what it believed to be effective climate change disclosure. "We liked some disclosure and didn't like other disclosure," Kumar said.

The good reports, she said, employ scenario planning exercises as part of a strategic review that evaluates the impact of climate risks into their long-term strategy.

Kumar highlighted a report issued by Statoil ASA, (STO) a Norwegian oil and gas company, as one that could be a model, partly because it had disclosed that it had allocated 15% to 20% of its capital expenditure by 2030 to new energy solutions in response to its scenario testing outcome.

"As a long-term investor, we understand that it takes time to pivot strategy and prepare for the future," Kumar said. "We like how Statoil provided a direct link between the impact of its scenario-planning exercise and strategic outcomes. This is what good looks like to us right now."

Kumar pointed to a strategic decision Pepsi made in the mid-2000s, to review its portfolio of products and consider health issues as an example of an effective pivoting strategy. "They allocated capital to acquire juice companies or to grow their non-carbonated beverage brands and invested in low-sodium or baked chips, responding to a trend of healthier living," she said.

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