 Zendesk Inc.s ZEN, 10.74 board on Thursday rejected an unsolicited takeover bid from Thoma Bravo LP and other private-equity firms in an all-cash transaction valued at 127 to 132 a share. Zendesk, which also faces a proxy fight from an activist investor seeking to torpedo its proposed purchase of SurveyMonkey parent company Momentive Global Inc. MNTV, -2.52 , issued the following statement: Consistent with its fiduciary obligations, after careful review and consideration conducted in consultation with its independent financial and legal advisors, the Board concluded that this non-binding proposal significantly undervalues the Company and is not in the best interests of the Company and its shareholders. 