Ontology Engineer (TS/SCI)

Vantor Inc.; Herndon (VA); On-site; USD 137,000 - 200,200; Full time

Benefits offered by this job

401(k) with company match

Mental health resources

Student loan repayment assistance

Adoption reimbursement

Pet insurance

Job summary

Vantor Inc. is looking for an Ontology Lead in Herndon, Virginia. The successful candidate will design, develop, and maintain domain-specific ontologies to support Object Based Intelligence mission requirements. The role requires a U.S. Citizenship and a TS/SCI security clearance.

The ideal candidate will have extensive experience with RDF, OWL, and SPARQL, along with leadership skills to mentor team members and engage with stakeholders. Vantor offers competitive benefits including 401(k) and mental health resources.

Qualifications

• Must be a U.S. citizen with active TS/SCI clearance.
• 12 years of relevant experience with an advanced degree or 17 years with a bachelor's.
• Experience in designing and implementing ontologies, taxonomies, or knowledge graphs.

Responsibilities

• Design, develop, and maintain domain-specific ontologies.
• Apply Semantic Web standards for data relationship modeling.
• Collaborate with analysts and Government stakeholders for mission needs.

Skills

Ontology Design

RDF

OWL

SPARQL

Data Modeling

Education

Advanced Degree related to Ontology

Job description

Vantor is forging the new frontier of spatial intelligence, helping decision makers and operators navigate what's happening now and shape what's coming next. Vantor is a place for problem solvers, changemakers, and go‑getters—where people are working together to help our customers see the world differently, and in doing so, be seen differently. Come be part of a mission, not just a job, where you can: Shape your own future, build the next big thing, and change the world.

To be eligible for this position, you must be a U.S. Citizen. This position requires an active U.S. Government security clearance, applicants who do not currently hold the required clearance will not be eligible for consideration. Employment for cleared roles is contingent upon verification of clearance status.

Export Control/ITAR: Certain roles may be subject to U.S. export control laws, requiring U.S. person status as defined by 8 U.S.C. 1324b(a)(3).

Please review the job details below.

This position requires an active U.S. Government Security Clearance at the TS/SCI level with CI polygraph.

Vantor is seeking an Ontology Lead to join our team. In this position you will design, develop, and maintain domain‑specific ontologies and knowledge models in support of Object Based Intelligence (OBI) mission requirements.

The Lead Ontologist serves as the technical authority for the design, development, and maintenance of domain‑specific ontologies and knowledge models that support Object‑Based Intelligence (OBI) mission requirements. This position applies semantic technologies and knowledge representation methodologies to enable data interoperability, advanced analytics, and knowledge integration across diverse data sources and object‑management systems. Leveraging Semantic Web standards, including RDF, OWL, and SPARQL, the Lead Ontologist develops scalable knowledge frameworks that enhance data discoverability, support AI/ML applications, and facilitate effective knowledge transfer to Government stakeholders.

Responsibilities:

• In coordination with domain experts, design, develop, and maintain domain‑specific ontologies, taxonomies, and knowledge graphs that support Object‑Based Intelligence mission objectives.
• Apply Semantic Web standards and technologies, including RDF, OWL, SHACL, and SPARQL, to model, represent, and query complex data relationships.
• Establish and maintain semantic data integration frameworks that enable interoperability across internal and external object‑management systems.
• Collaborate with analysts, data scientists, engineers, and Government stakeholders to capture requirements and translate mission needs into formal knowledge models.
• Develop and maintain ontology governance processes, standards, documentation, and version‑control practices to ensure consistency and scalability.
• Support AI/ML initiatives by providing structured knowledge representations that enhance model explainability, interpretability, and contextual reasoning.
• Conduct ontology validation, testing, and quality assurance activities to ensure accuracy, completeness, and alignment with mission requirements.
• Provide technical leadership, mentoring, and knowledge transfer activities to Government personnel and project team members on ontology development methodologies and semantic technologies.

Minimum Qualifications:

• Must be a U.S. citizen and have an active TS/SCI with CI polygraph.
• 12 years of experience and an advanced degree or 17 years of experience with a bachelor's degree.
• Demonstrated experience designing and implementing ontologies, taxonomies, or knowledge graphs in operational or research environments.
• Experience applying Semantic Web technologies, including RDF, OWL, and SPARQL.
• Knowledge of ontology engineering methodologies, data modeling principles, and semantic interoperability frameworks.
• Ability to communicate complex technical concepts effectively to both technical and non‑technical stakeholders.

Preferred Qualifications:

• Experience developing and maintaining enterprise knowledge graphs and integrating heterogeneous data sources.
• Familiarity with AI/ML workflows and the use of ontologies to improve model explainability, reasoning, and decision support.
• Experience providing technical leadership, mentoring, and formal knowledge transfer to Government personnel or large multidisciplinary teams.
• Certified Data Management Professional (CDMP) or equivalent data architecture certification.
• Certified Knowledge Manager (CKM) or comparable knowledge management credential.
• Formal training or certification in Semantic Web technologies, knowledge graphs, ontology engineering, RDF, OWL, or SPARQL.

Pay Transparency:

To support pay transparency, Vantor includes salary ranges in all U.S. job postings. Starting pay for this role will fall within the listed range and will be based on factors such as experience, qualifications, skills, location, and market conditions. Candidates who meet the minimum requirements for the role should not expect to receive compensation at the top of the range. The listed range reflects the expected pay for this position, and final offers will be determined based on each candidate's experience, expertise, and alignment with the role.

The base pay for this position within the Washington, DC metropolitan area is: $137,000.00 – $182,000.00 – $200,200.00 annually.

For all other states, we use geographic cost of labor as an input to develop market‑driven ranges for our roles, and as such, each location where we hire may have a different range.

Benefits:

Vantor offers a competitive total rewards package that goes beyond the standard, including a robust 401(k) with company match, mental health resources, and unique perks such as student loan repayment assistance, adoption reimbursement, and pet insurance to support all aspects of your life. More information on our benefits can be found at https://www.Vantor.com/careers.

EEO Policy:

EEO Policy: Vantor is an equal opportunity employer committed to an inclusive workplace. We believe in fostering an environment where all team members feel respected, valued, and encouraged to share their ideas. All qualified applicants will receive consideration for employment without regard to race, color, religion, national origin, sex, gender identity, sexual orientation, disability, protected veteran status, age, or any other characteristic protected by law.