BlackRock MuniVest Fund, Inc. is a closed-ended fixed income mutual fund launched by BlackRock, Inc. It is managed by BlackRock Advisors, LLC. The fund invests in the fixed income markets of the United States. It primarily invests in investment grade, long term municipal obligations that are exempt from federal income taxes. The fund seeks to invest in securities with maturities of more than ten years. BlackRock MuniVest Fund, Inc. was formed on September 29, 1988 and is domiciled in the United States.

Ribbon Communications, Inc. delivers communications software, IP and optical networking solutions to service providers, enterprises, and infrastructure sectors. It operates through the Cloud and Edge and IP Optical Networks segments. The Cloud and Edge segment offers secure and reliable software and hardware products, solutions, and services for enabling Voice over Internet Protocol communications, Voice over Long-Term Evolution and Voice Over 5G communications, and Unified Communications and Collaboration within service provider and enterprise networks and from the cloud. The IP Optical Networks segment secures reliable hardware and software products solutions for IP networking, switching, routing, and optical transport designed to support and enable technologies like 5G, distributed cloud computing and corresponding applications by delivering ultra-low cost-per-bit transport and multi-service flexibility. The company was founded in 1997 and is headquartered in Plano, TX.