Of 88 top Fortune 500 companies contacted by the center, 45 had implemented such policies — up from 36 in a survey of the same firms a year before.
The move toward voluntary disclosure comes amid a sharp public debate over the political influence of corporations, which under a 2010 Supreme Court ruling are now allowed to spend unlimited funds on federal elections.
The decision has opened a floodgate of spending by super PACs and other political groups unbound by contribution limits, fueled in part by large donations from companies. Much of the activity is conducted in secret, however, because trade and other nonprofit groups do not have to reveal their donors to the Federal Election Commission.
The U.S. Chamber of Commerce and other business groups, which spend primarily in support of Republicans, have opposed calls by Democrats to require such disclosure.
“Despite the fierce attack on public disclosure policies over the past year, companies continue to adopt disclosure, and it’s going along at a very steady pace,” said Bruce Freed, president of the Center for Political Accountability. “Companies are viewing this not just as good business practice but as protection.”
Dozens of companies have been swept up in public controversies in recent years over their political spending, including a boycott against the Target retail chain in 2010 after a corporate donation made its way to an anti-gay gubernatorial candidate.
Over the past two years, shareholder groups have ratcheted up pressure on companies to disclose the money they spend on lobbying and political campaigns. Dozens of companies no longer back a conservative lobbying group, the American Legislative Exchange Council, because of its support of controversial gun legislation and other policies.
Chick-fil-A, the privately held fast-food chain, was also the target of boycotts and rallies of support over the summer because of its conservative owner’s financial support for groups that oppose gay marriage.
Business groups such as the chamber, which plans to spend up to $100 million on congressional and state races this year, have accused critics of mounting an intimidation campaign to force disclosure. Senate Minority Leader Mitch McConnell (R-Ky.) accused President Obama and other Democrats of seeking to use disclosure to create political enemies’ lists akin to those kept by President Richard M. Nixon.
Interest groups funded by secret donations, including Crossroads GPS, Americans for Prosperity and the U.S. Chamber of Commerce, have spent more than $200 million so far this cycle on federal political ads, nearly matching the spending from super PACs, which must reveal their donors, according to tracking data.
In its study, the Center for Political Accountability focused on the top echelon of the Fortune 500, finding that 93 of 196 companies it studied made “some disclosure of their direct political spending,” including money given to political candidates, parties or interest groups. An additional 22 companies said their policy is not to engage in any political spending, the study found.
In addition, 70 companies disclose their payments to trade associations, and nine say they ask business groups not to use their money for political purposes, the study found.
The move to volunteer more details about political spending comes in part as companies seek to avoid public-relations trouble that could hurt their bottom lines, the study authors said.
“Most of them are very aware of how their brand names could become conflicted with public issues,” said Sol Kwon, the center’s associate director. “They’re very aware that it’s a very edgy landscape out there, and there’s a greater spotlight on companies and how they’re spending money.”