(Reuters) - Barnes & Noble Inc said on Friday it entered into an employment agreement with Chief Executive William Lynch to continue in his post for another two years, according to a filing.

The largest U.S. bookstore chain said Lynch will receive the same compensation and benefits as before, but get an additional cash bonus of $1.8 million for his role in attracting investments from Microsoft Corp and Pearson PLC in forming Nook Media LLC, according to the filing with the U.S. Securities and Exchange Commission.

The agreement provides Barnes & Noble with the right to assign Lynch as chief executive of Nook, the company's e-reader and tablet business, if the company is separated.

Lynch would receive a cash retention bonus of $1.5 million in that case. (SEC filing: http://link.reuters.com/zur56t)

The company said in February that its Chairman Leonard Riggio planned to make an offer for the main bookstore business, but not its Nook and e-book business and its college bookstores.

Barnes & Noble said it would evaluate the sale of its retail business.

Barnes & Noble Inc reported a quarterly net loss in February, due to a sharp decline in sales in its Nook device and e-books business, as well as lower sales at its bookstores and college bookstore chain.

(Reporting by Vrinda Manocha in Bangalore; Editing by Lisa Shumaker)