PLANO, Texas--(BUSINESS WIRE)--Spok Holdings, Inc. (NASDAQ: SPOK), a global leader in healthcare communications, today announced the entry into an agreement to sell certain narrowband spectrum licenses in its two-way paging inventory to Sensus USA, a designer and manufacturer of metering and automatic meter-reading products catering to municipal and industrial markets worldwide. The purchase price is $8 million, with a portion of the consideration deferred until existing Spok users have been mi