Whitney has begun a tender offer for up to 49.5 million shares at $21.50 in cash.
Ratners began a tender offer on Tuesday for the two Kay bond issues, which have a total face value of $150 million.
Olympia & York began a tender offer to increase its stake in the company by up to 14 million shares.
Allegis will begin an $80-a-share tender offer for 63 percent of its shares.
Bond began a hostile tender offer on Sept. 4 for $38 a share.
Pirelli has begun a $58-a-share, $1.86 billion tender offer.
That could prevent him from beginning a tender offer for more G.M. shares.
Barring that, though, Ingersoll is prepared to begin a tender offer, he said.
In the first step, a Green subsidiary will begin a tender offer for 49.9 percent of the company.
Two weeks ago, Mr. Jacobs threatened to begin a tender offer for the 87.6 percent of the company he does not already own.