Another large shareholder has come out against the status quo at PDL BioPharma (NASDAQ:PDLI). In a letter written to PDL's board of directors, Highland Capital called for the immediate resignation of PDL's chairman of the board, L. Patrick Gage. It also called for the immediate departure from the company of CEO Mark McDade, who is already resigning by the end of the year.

Highland wants him gone sooner though because it views McDade as an "impediment to the strategic review process," which is the process by which PDL and advisor Merrill Lynch are determining what it should do with some of its assets. The letter was dated yesterday.

Highland reiterates in the letter what many, like myself, have come to believe about PDL's assets, when it writes that "shares are trading at a sizeable discount to the private-market value of the underlying assets" and that it believes "shares of PDL are currently priced at a value ranging from a modest premium to a slight discount to the private-market value of the company's royalty stream." Like other PDL investors, it has called for a sale or breaking apart of these assets in the hopes that the sum of their parts will be worth more than what they are currently being valued at.

Highland owns approximately 4.7% of PDL's shares. Other large shareholders, such as hedge fund Third Point, have also argued for change at PDL. Throw in SAC Capital, a fund that owns shares of PDL and which has aligned with Third Point in the past on drugmakers such as Acorda Therapeutics (NASDAQ:ACOR), and it means that investors with at least 26% of shares outstanding will be voting for a change at PDL when the next three board seats are up for grabs in June or July.

Others such as PDL co-founder Cary Queen also have convincingly voiced an opinion against current management at PDL, so those hoping for change and a breaking up or sale of PDL look like they will be getting their way soon enough. 

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Fool contributor Brian Lawler does not own shares of any company mentioned in this article. The Fool holds a majority stake in its disclosure policy.