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Mark R.S. Foster

Foster, Mark R.S.


San Francisco, (415) 268-6335


University of California, Davis (B.A., 1996)
Santa Clara University School of Law (J.D., 2002)

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Mark Foster is a partner in Morrison & Foerster’s San Francisco office. He focuses on representing public companies, and their directors and officers in securities fraud class actions, shareholder derivative lawsuits, and special investigations. Mr. Foster routinely defends clients against investor lawsuits that allege violations of federal and state securities laws, breach of fiduciary duty, and insider trading. Mr. Foster has extensive experience with litigation under the Securities Act of 1933, the Securities Exchange Act of 1934, the Private Securities Litigation Reform Act, the Securities Litigation Uniform Standards Act, the California Corporations Code, and Delaware corporate law.  Mr. Foster has won dispositive pre-trial motions, prevailed on the merits at trial, and preserved victories on appeal.

Mr. Foster graduated first in his class from Santa Clara University School of Law, Order of the Coif. While in law school, he was a Dean’s Fellow with a full-merit scholarship, served as senior production editor of the Santa Clara Computer High Technology Law Journal, and earned American Jurisprudence Awards in seven subjects.

Mr. Foster’s representative engagements include the following:

  • The successful defense of AspenBio Pharma, Inc. and certain of its directors and officers in a securities class action that challenged the accuracy of statements regarding a developing technology to rule out appendicitis in certain types of patients.  The dismissal of the case in full was affirmed by the Tenth Circuit Court of Appeals.  See Wolfe v. AspenBio Pharma, Inc., 2014 WL 5293685 (10th Cir. Oct. 17, 2014)
  • The successful defense of The Clorox Company and certain of its directors in the defense of a shareholder class action that challenged the accuracy of proxy statement disclosures regarding say-on-pay executive compensation and a proposed increase to the number of authorized shares for a stock incentive plan.  After defeating an attempt to enjoin the company’s annual meeting, the defendants prevailed on the merits at trial on a fully developed factual record.  See Mancuso v. The Clorox Co., No. RG12-651653 (Cal. Super. Ct. Alameda Cnty.).
  • The successful defense of Yahoo! Inc. and certain of its former directors and officers in connection with allegations relating to alleged false statements and alleged breaches of fiduciary duty.  After the case was dismissed, Mr. Foster argued the plaintiff’s appeal before the California Court of Appeal for the Sixth District, which affirmed dismissal of the case with prejudice.  See Leyte-Vidal v. Semel, 220 Cal.App.4th 1001 (2013).
  • The successful defense of Yahoo! and certain of its officers in securities class actions that were dismissed with prejudice in In re Yahoo! Inc. Securities Litigation, 2012 WL 3282819 (N.D. Cal. Aug. 10, 2012) and Brodsky v. Yahoo!, Inc., 630 F. Supp. 2d 1104 (N.D. Cal. 2009);
  • The successful defense of a publicly-traded technology company and its former chairman against allegations of civil securities fraud in connection with an initial public offering in a six-week jury trial that resulted in a complete defense verdict;
  • The successful defense of directors and officers of one of the world’s largest contact lens manufacturers in a securities class action;
  • The successful defense of a global pharmaceutical company in securities litigation that was dismissed with prejudice;
  • The successful representation of a consumer-products conglomerate and its directors and officers in defense of a shareholder’s derivative lawsuit;
  • The ongoing defense of a semiconductor manufacturer and certain of its executives in a securities fraud class action;
  • The representation of the audit committee for a publicly-traded company in connection with stock option granting processes and practices;
  • The representation of clients in the defense of shareholder lawsuits challenging mergers and tender offers; and
  • The representation of clients in connection with investigations by the Securities and Exchange Commission.