Barnes & Noble continues to draw the interest of outside investors. In a filing with the Securities & Exchange Commission yesterday, Aletheia Research & Management reported that it now owns more than 10 million shares of the retailer giving it a 17.5% stake in B&N. Aletheia acquired nearly 2 million shares of B&N in the January 21 to January 29 period, paying more than $41 million for the shares. In all, the firm has paid more than $210 million for its B&N stake.

The filing comes a week after it was disclosed that investor Ron Burkle sent a letter to the B&N board questioning its November passage of a poison pill designed to discourage outside investors from accumulating too big a position in B&N. Burkle, who owns 18.7% of B&N’s shares through his Yucaipa funds, asked the board to waive the rule to permit him to acquire up to a 37% stake in the bookseller. The poison pill is triggered if a shareholder owning more than 20% of B&N stock acquires additional shares.