NEW YORK--(BUSINESS WIRE)--Halper Sadeh LLC, an investor rights law firm, is investigating whether the sale of Middlefield Banc Corp. (NASDAQ: MBCN) to Farmers National Banc Corp. for 2.6 shares of Farmers common stock per share of Middlefield common stock is fair to Middlefield shareholders. Halper Sadeh encourages Middlefield shareholders to click here to learn more about their legal rights and options or contact Daniel Sadeh or Zachary Halper at (212) 763-0060 or sadeh@halpersadeh.com or zha. ...