 ALEXANDRIA, Va.--BUSINESS WIRE--Spok Holdings, Inc. NASDAQ: SPOK, a global leader in healthcare communications, today announced results for the second quarter ended June 30, 2021. In addition, the Companys Board of Directors declared a regular quarterly dividend of 0.125 per share, payable on September 10, 2021, to stockholders of record on August 17, 2021. Key Second Quarter 2021 Operating Highlights: Second quarter 2021 software revenue of 15.9 million included 9.6 million of maintena 