PDL BioPharma, Inc. seeks to provide return for its shareholders by acquiring and managing a portfolio of companies, products, royalty agreements and debt facilities in the biotechnology, pharmaceutical and medical device industries. The Company's segments include income generating assets and product sales. The income generating assets segment consists of royalties from issued patents in the United States and elsewhere, covering the humanization of antibodies, which it refers to as the Queen et al. patents; notes and other long-term receivables, royalty rights-at fair value and equity investments. The Company's product sales segment consists of revenue derived from Tekturna, Tekturna HCT, Rasilez and Rasilez HCT (collectively, the Noden Products or Tekturna) sales. It is focused on the acquisition of additional products. As of December 31, 2016, it had a total of five notes receivable transactions outstanding and one note/royalty (hybrid) receivable transaction outstanding.