It is the latest salvo in a four-year campaign by Dutch fund group PGGM and Britain's Railways Pension Trustee Company Ltd, known as Railpen, against Ellison and his company's governance, which has so far brought no response at all from Oracle, and only limited support from other shareholders.

In a letter addressed to the Oracle board that was seen by Reuters, the shareholders demanded that Oracle "address board accountability by implementing proxy access" and "implement a compensation structure that shareholders can support". The funds said they would send the letter to the U.S. Securities and Exchange Commission on Monday.

Oracle did not immediately return a request for comment on Sunday.

Both PGGM and Railpen have campaigned for years for easier access to Oracle's board and have opposed Ellison's compensation, which last year totalled $67 million (45 million pounds), according to Oracle's proxy filing.

Ellison, who founded in 1977 the company that became Oracle and only last year stepped down as CEO to become executive chairman, owns about 25 percent of the company's shares, according to Thomson Reuters data.

By comparison, the campaigning fund groups have a miniscule share. PGGM owns 0.08 percent of Oracle's shares, according to Thomson Reuters data. It was not immediately clear how many shares Railpen holds.

Last year Railpen worked with a number of other pension investment groups to get a "proxy access" measure onto the ballot at Oracle's shareholder meeting, which proposed that shareholders would have the power to nominate candidates to join the board.

The proposal, which Oracle and Ellison opposed, was defeated, although PGGM and Railpen say it had the support of 68 percent of votes from shareholders outside of Oracle itself. At the same meeting, an advisory vote on Oracle's executive pay was defeated, but the company made no changes as a result.

It is not clear that the pension funds' latest attempt to engage Oracle will be any more successful than previous forays.

"Over the past four years, PGGM and Railpen have together written several letters to certain directors to begin a constructive dialogue for addressing our governance concerns," said the latest letter. "Despite numerous attempts over this period, no meeting with any director has been forthcoming."

(Reporting by Bill Rigby in Seattle, Luc Cohen in New York and Supriya Kurane in Bangalore; Editing by Muralikumar Anantharaman)