Mario J. Ranieri III was born in Port Arthur, Texas September 21st, 1993. He is married wife Amanda and has 2 Sons. He enlisted in the United States Marine Corps and reported to MCRD Parris Island, South Carolina in August 2012. He then went to Marine Combat Training in Camp Geiger, North Carolina November through December of 2012. From that point he went to 29 Palms, California, where he earned the MOS 0651(Data Systems Administrator) and was promoted to Lance Corporal on March 1st, 2013.

Lance Corporal Ranieri arrived to his first command, 1st Battalion, 2nd Marine Regiment, 2nd Marine Division, II MEF, aboard Camp Lejeune, NC in July 2013. Where he deployed to Afghanistan in Support of Operation Enduring Freedom in 2014. During this deployment he was promoted to Corporal July 1st, 2014. Corporal Ranieri then deployed to Japan and Korea as part of the Unit Deployment Program – East (UDP-E) from 2015-2016. During this period, he was promoted to Sergeant November 1st, 2015.

August of 2016, Sergeant Ranieri executed orders to Marine Wing Support Squadron 372, Marine Aircraft Group(MAG) 39, 3rds Marine Aircraft Wing(MAW), I MEF aboard Camp Pendleton, California. He then deployed to Kuwait in support of Special Purpose MAGTF – Crisis Response – Central Command in 2017. During this deployment he served as Alpha Company Data Chief. In October 2017 his MOS changed from 0651(Data Systems Administrator) to 0671 (Data Systems Administrator).  When Sergeant Ranieri returned, he assumed the billet of Platoon Sergeant for the S-6 that consisted of 45 Marines. He was then promoted to Staff Sergeant on January 1st, 2020, and became his current MOS 0679 (Data Systems Chief).

March 2020 Staff Sergeant Ranieri reported to MAG 14, 2nd MAW, II MEF aboard Marine Corps Air Station Cherry Point. Where he served as Communications Chief until receiving orders to Communications Company, Combat Logistics Regiment 27, 2nd Marine Logistics Group, II MEF aboard Camp Lejeune in November 2021. While with Communications Company, he served as 3rds Platoon Data Chief.
August 2023 Staff Sergeant Ranieri reported to Task Force 51, 5th Marine Expeditionary Brigade aboard NSA 2 in Manama, Bahrain, where he served as Data Chief and C2 Systems Integrator, supporting multiple joint force and partner nation operations. Staff Sergeant Ranieri then attended Data Chiefs Supervisors Course in 29 Palms, California in July 2024.

As of August 2024, he is currently serving as Data Systems Chief and Information Systems Security Manager (ISSM) for the Command Element, 26th Marine Expeditionary Unit, II MEF aboard Camp Lejeune. He was the Data Systems Chief and ISSM for the 26th MEU SPMAGTF during 2025 which included V2/2, CLB-22, and VMM 261.