According to the Complaint, Portola Pharmaceuticals, Inc. is a biopharmaceutical company that develops and commercializes treatments for thrombosis and other hematologic diseases. Its lead product is Andexxa, marketed as Ondexxya in Europe. Andexxa is for patients treated with rivaroxaban or apixaban, when anticoagulation needs to be reversed due to life-threatening or uncontrolled bleeding.

The Complaint alleges that throughout the Class Period, Defendants made materially false and/or misleading statements, as well as failed to disclose material adverse facts about the Company's business, operations, and prospects. Specifically, the Complaint alleges Defendants failed to disclose to investors: (1) that Portola's internal control over financial reporting regarding reserve for product returns was not effective; (2) that Portola was shipping longer-dated product with 36-month shelf life; (3) that Portola had not established adequate reserve for returns of prior shipments of short-dated product; (4) that, as a result, Portola was reasonably likely to need to "catch up" on accounting for return reserves; and (5) that, as a result of the foregoing, Defendants' positive statements about the Company's business, operations, and prospects were materially misleading and/or lacked a reasonable basis.