In Manti Holdings LLC et al v. Authentix Acquisition Company, Inc., the Delaware Court of Chancery held a stockholder could waive appraisal rights in a stockholders agreement. The Court noted:

• The stockholders agreement was not a contract of adhesion. Sophisticated parties were involved and were represented by counsel, and counsel exchanged drafts of the proposed stockholders agreement before agreeing to a final contract.
• There is no record evidence that the petitioners were not fully informed.
• The Delaware General Corporation Law, or the DGCL, does not explicitly prohibit contractual modification or waiver of appraisal rights, nor does it require a party to exercise its statutory appraisal rights. Thus, such modification or waiver serves to supplement the DGCL, and is not inconsistent with, nor contrary to, the DGCL.
• The stockholders agreement clearly and unambiguously waived appraisal rights.
• The Court did not decide whether a waiver of appraisal would be upheld in other circumstances.