NEW YORK, March 17, 2011 /PRNewswire/ — Having been buffeted by sustained attacks by activists and proxy-voting advisors over the past years, shareholder rights agreements (also known as "poison pills") are no longer prevalent, but recent case law shows they can still be valuable anti-takeover devices, concludes the most recent installment of The Conference Board Director Notes series, Poison Pills in 2011.

The recent Air Products v. Airgas case shows that poison pills that are properly structured, adopted and administered can still protect companies from a hostile takeover if corporate boards review their companies' governance profile and address a number of specific issues.

"It will be interesting to watch for changes in poison pill activity taking place this proxy season, as companies react to the most recent developments in case law, hedge funds get back into the activism game, and M&A activity continues to grow," says Andrew L. Bab, a partner in Debevoise & Plimpton LLP's New York office and co-author of the report for The Conference Board.