BOSTON — Activists pressing mutual fund firms to adopt so-called "genocide-free" investment policies have won an initial victory that's expected to bring such a proposal before shareholders of Fidelity Investments' biggest equity fund and others in coming months.

Four other big fund companies are also targeted in a campaign emboldened by a Securities and Exchange Commission staff decision this past week.

The decision is expected to prevent Fidelity from blocking shareholder votes at several of its funds, including a March 19 shareholder meeting for Fidelity's $81 billion Contrafund.

Observers say the SEC staff finding also could trigger similar votes at Barclays, Franklin Templeton, T. Rowe Price, and Vanguard — the other firms that have received shareholder proposals authored by Boston-based Investors Against Genocide.

The proposals would require fund boards to direct managers to screen out investments that the board determines are tied to human-rights violations and genocide in places like Sudan's Darfur region.

Boston-based Fidelity, the nation's largest mutual fund firm, asked SEC staff in November for assurance that it wouldn't recommend enforcement action against the company if it left the proposal off shareholder ballots.

The SEC staff was "unable to concur" with Fidelity's arguments that the proposal didn't meet criteria to bring it before shareholders, according to a letter Tuesday from SEC legal counsel. The letter didn't offer details of the staff's position, which SEC commissioners could overrule if the issue comes before them.

Fidelity spokesman Vincent Loporchio said Thursday, "Although the SEC staff has not concurred with our position, we continue to believe the proposal deals with matters relating to a fund's ordinary business operations, and contains false and misleading statements. The SEC rules permit the exclusions of shareholder proposals if they meet those criteria."

SEC spokesman John Nester declined to say whether the staff's rejection of Fidelity's request would apply to other fund companies. Such requests are considered on a case-by-case basis, he said.

Eric Cohen, chairman of Investors Against Genocide, called the SEC finding a precedent-setting move that will leave Fidelity and other firms little choice but to bring the proposals before shareholders.

Some firms including Fidelity have recently established funds that seek out investments meeting certain social criteria. But most funds require directors and managers to maximize returns.

Dan Lefkovitz, lead Fidelity analyst at Morningstar Inc., predicted Fidelity shareholders would defeat the activists' proposal.

"Fidelity has never purported to use any social criteria in choosing its investments," he said.

Eric Tyson, author of the book "Mutual Funds for Dummies" and a former management consultant, agreed chances of passage are slim.

"But to the extent that Fidelity feels forced to put this before shareholders, this organization is getting some attention to the issue, and Fidelity will have to take a stand," Tyson said.

Cohen's group and others have recently targeted mutual fund firms including Fidelity over their current or past holdings in companies the groups say are linked to genocide, such as PetroChina Co., which has been active in the oil industry in Sudan, the African nation accused by the U.S. government of complicity in genocide.