At this time of year, the word "proposal" may conjure up a plethora of annoying Valentine's Day commercials. But many investors know the word "proposal" can mean something far less romantic. Shareholder proposals are increasingly challenging corporate management teams to change their ways.

Props and proposals
A shareholder proposal, also known as a shareholder resolution, allows an investor or a group of investors to recommend certain policy changes at a company's annual meeting; shareholders can find these proposals at the end of the proxy statements they receive in the mail, and vote for or against the proposals by mailing their paper ballots (or using an online service).

For years, businesses and investors tended to dismiss shareholder proposals as insignificant and doomed. But new rules passed as part of the recent financial reform laws, including as the requirement that public corporations grant their shareholders an advisory vote on compensation, have suddenly given shareholders a greater voice -- and a better shot at success.

Last year, several historic votes at public companies revealed increased feistiness among shareholders, as both Motorola (NYSE: MOT) and Occidental Petroleum (NYSE: OXY) lost say-on-pay votes.

Now, investors are asking the company that once urged its customers to "think different" to do so itself. Apple (Nasdaq: AAPL) has become the latest company to get poked by a shareholder proposal. The Central Laborers' Pension Fund of Jacksonville, Illinois, seconded by major proxy advisory firm Institutional Shareholder Services, is demanding an annual succession plan for the time when CEO Steve Jobs no longer leads the company.

It's a timely issue for Apple shareholders, given Steve Jobs' health issues and Apple's controversial lack of transparency about his medical condition. (In fairness, many argue that Jobs is entitled to health-related privacy just like the rest of us are.)

Monitoring the proceedings
If you're curious about this and other shareholder proposals, check out public companies' proxy statements using the SEC's database, or visit ProxyMonitor.org from The Manhattan Institute. The site recently released interesting data about shareholder resolutions over the last several years.

ProxyMonitor's report chronicles the eight largest recipients of shareholder proposals in the 2008-2010 timeframe. Not surprisingly, the largest, most well-known companies really seem to rack up the shareholder criticism. ExxonMobil (NYSE: XOM) received 39 resolutions in that timeframe, while Citigroup (NYSE: C) fielded 26, and Bank of America (NYSE: BAC) got 23.

More than 5% of all proposals came from one of two unions, the AFL-CIO and the American Federation of State, County, and Municipal Employees. That union backing may explain why some investors may react negatively to a lot of shareholder proposals, even if they call for reasonable new policies.

Interestingly, large institutional shareholders and hedge funds aren't as active in this regard as you might think. Insrtead, individuals, unions, and religious and other issue-advocacy groups make up the six most active sponsors of shareholder proposals.

The report also revealed that fairly simple and straightforward corporate governance-related proposals enjoyed the strongest adoption rate over that timeframe, at 19%; only 7% of executive compensation proposals got adopted. Although many shareholder proposals deal with social policy (38%), shareholders were unimpressed; none of those recommendations was adopted.

Succession and success
It's time to gear up for another pivotal proxy season, with shareholder votes in the spotlight. That probably explains the recent emergence of services like ProxyMonitor.org's user-searchable database, as well as websites like Moxy Vote, a beta service that allows shareholders to engage in online proxy voting and follow shareholder activists.

As for Apple, the succession-plan proposal isn't even the first major shareholder pushback it's received in the past year. At the end of 2010, CalPERS announced plans to file a resolution seeking majority voting at Apple.

It should be interesting to see whether the majority of Apple shareholders agree with either of the proposals on the table. Beyond the goings-on in Cupertino, I'm even more interested to see whether shareholders' increasing activism helps 2011 top the success rates for proposals seen over the past two years.

Check back at Fool.com every Wednesday and Friday for Alyce Lomax's columns on corporate governance.