The International Corporate Governance Network (ICGN) has joined the investors and academics who are asking the U.S. Securities and Exchange Commission to require companies to provide more disclosure about their political spending. 

The ICGN, whose members have more than $18 trillion in assets under management, has sent a letter to the SEC that supports a rulemaking petition filed by 10 law and business school professors. 

“The ICGN recognises that corporate political activity can be positive. However when corporate resources are deployed to seek political influence there is also potential for abuse. In the extreme this can lead to serious breaches of business ethics, particularly when influence is sought through corrupt practices or in ways that are not consistent with promoting the long-term interests of the company and its investors,” the London-based group wrote in its Aug. 10 letter. 

U.S. companies are not required to disclose their political contributions in their proxy materials, but some large companies, such as Merck, Hewlett-Packard, Aetna, and Microsoft, have voluntarily provided greater disclosure in response to shareholder demands, which include a multiyear shareholder proposal campaign coordinated by the Center for Political Accountability.

In related news, Starbucks CEO Howard Schultz has enlisted more than 100 current and former chief executives in his campaign to stop making personal contributions to lawmakers until they address the U.S. government’s mounting debt. Among the executives who have supported this effort are those at AOL, J. Crew, JC Penney, and Whole Foods Market, according to CNN Money. While this effort is attracting media attention, it appears unlikely that Schultz’s campaign will discourage investors from filing shareholder proposals that seek more disclosure of corporate political spending. 

Meanwhile, ISS’ Governance Exchange plans to hold a Sept. 27 webcast, “Show Me the Money: The Debate Over Corporate Political Spending Disclosures.” The webinar’s panelists will discuss proposed legislation and preview the shareholder resolutions expected during the 2012 proxy season. The panelists will include: Matthew Lepore, vice president and chief counsel for corporate governance at Pfizer; David Katz, a partner with the law firm of Wachtell, Lipton, Rosen & Katz; Bruce Freed, president of the Center for Political Accountability; and Adam Kanzer, managing director and general counsel at Domini Social Investments. The panel will be open only to Governance Exchange members. For more details, click here.