The pension fund owns about 2 million Caterpillar shares, worth about $177 million.
New York Comptroller Thomas DiNapoli has proposed a resolution that would allow fellow Caterpillar shareholders to demand changes in the company's sales practices.
The Securities and Exchange Commission recently rejected a corporate proposal to omit the resolution from proxy materials.
A Caterpillar spokesman declined to discuss any proxy statement before it's issued.
The shareholder meeting is scheduled June 12.
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