(Adds details from filing, last week's ISS report)
BOSTON, Oct 30 (Reuters) - Billionaire investor William Ackman on Monday accused Automatic Data Processing of providing misleading and incorrect data to Institutional Shareholder Services and asked the proxy advising firm to reconsider its recommendations.
"ADP provided non-public, inaccurate and misleading information, claims, and arguments which were relied upon by ISS," Ackman said in a regulatory filing made with the U.S. Securities and Exchange Commission.
"ISS accepted, and in its Report has publicly endorsed, certain misleading or incorrect factual assertions made by ADP management during its engagement with ISS," Ackman said in the filing.
The filing came less than one week after ISS issued a report to guide institutional investors in next week's proxy vote where Ackman hopes to win three seats on the human resources outsourcing company's board.
Last week ISS wrote that shareholders should withhold their vote for ADP director Eric Fast to make room for Ackman to join the board. But the report also said that Ackman's case was not "sufficiently compelling to justify replacing three directors."
In the filing Ackman sid that ISS failed to follow its own guidelines which say that it relies only on publicly disclosed information to reach its recommendations. In the ADP matter, which is fast becoming the most bitter proxy fight of the season, the hedge fund manager said that ISS used the "non-public and false and misleading information" that ADP provided.
ADP had no immediate comment.
Ackman has criticized the company for what he calls sluggish earnings and operating inefficiently. (Reporting by Svea Herbst-Bayliss; Editing by Andrew Hay)