Earlier this month, Neff reported Untied Rentals proposed the acquisition of all the Miami-based company's outstanding shares in exchange for .18 shares in the Connecticut company. Neff disclosed then it simply formed a committee of independent directors to consider the offer.

In separate lawsuits, shareholder-plaintiffs Jay Leonard, Howard V. Ogel, Paul Berger, Mary Jane Crescente and the Gordon McCormick individual retirement account, Ivette Chinigo, Simon Katz, Rose Katz and Jason Kerrigan claim Neff breached fiduciary responsibilities owed to investors by agreeing to the merger.

Besides Neff, listed as defendants are Neff directors Jorge Mas Jr., Juan Carlos Mas and Jose Ramon Mas, along with United Rentals , General Electric Capital Corp. and Santos Fund. Jorge Mas also serves as chief executive officer of MasTec Inc., the Miami-based telephone and cable construction company.

In a prepared statement, Neff argues the complaints are without merit. Because they claim the proposed merger is unfair to individual shareholders, the eight petitions are asking the Delaware court to prohibit the consummation.

News of the lawsuit apparently had a greater impact on publicly traded shares of United Rentals, which last traded down 44 cents at $15.56 about an hour after the markets opened on Wednesday. Neff last traded Tuesday unchanged at $2.50 a share.