Executive Team

We Protect Multifamily Property Owners From Unfair Insurance Companies

Founder / CEO

Mark A. Deddens

visionary, innovator, results fanatic

Visionary leader and entrepreneur with over 35 years of proven success; growing shareholder value, customer loyalty, and bottom line results for diverse business to business services.

Passionate about building relationships and adopting new concepts that better himself, his company and his client’s experience. Exceeding client expectations has always been in the forefront of his mission.

The iStorm Group vision, mission and specialties focus on creating peace of mind amidst chaos, decreasing costs and increasing profit margins for our clients.

Mark’s areas of expertise include understanding / embracing our customers’ core challenges and goals, identifying problems / deficiencies in the multifamily claims settlement processes, and creating actionable plans that provide a viable and profitable solution to those challenges.

CEO, Drew and Cole Deddens Foundation

Tammy Deddens

practical, friendly, team builder

Tammy is a caring and passionate mother / person with a knack for helping people.

Tammy and Mark lost twin sons in December of 2010. In the spirit of their love of all children the Drew and Cole Deddens foundation was formed. The foundation provides support to multiple needy children and families in communities throughout the US.

To further this personal mission, Tammy is also highly involved with iStorm Group’s Corporate Social Responsibility (CSR) program, through which iStorm Group donates a percentage of its net profits each year. The foundation will support St. Jude and Nationwide Children’s in Columbus Ohio. Both organizations give the gift of hope to millions of children who receive lifesaving care every year. Each and every child deserves the chance for a healthy future, and iStorm Group is committed to this mission with Tammy leading this initiative. Learn more about the Drew and Cole Deddens foundation here.

Chief Operating Officer

Elizabeth Bashore

detailed, exacting, results driven

With 20+ years of managerial, administration, and customer service & satisfaction experience, Liz provides the optimal client experience. Giving the utmost in personal attention to your staff and properties. She is very personable, organized, efficient, detail oriented, and excels at multi-tasking. Liz is very eager to do everything necessary to ensure the client has the best experience with the least amount of stress before, during, and after your large loss events.

Elizabeth has a degree in mathematics from Indiana University with minors in accounting, finance, and economics. When not busy with ISG, Liz enjoys gardening, home projects, and her three children and husband.

VP Client Relations + Development

Seth Deddens

pragmatic, dependable, results driven

Seth has a solid background in professional, consultative, client management. He believes that success is built upon strong relationships, dedication and constant perseverance. Seth has been responsible for 25 million dollars in net sales while collaborating with ISG clients during the last 5 years.

Seth’s responsibilities include developing and maintaining, strong, viable partnerships with iStorm Group Clients. His primary objective is to understand and fully embrace each Clients long term vision, mission and goals, and ensure our services support and emulate their objectives. Routinely and objectively listening to client feedback and bringing those ideas back to the Executive team for consideration, is also paramount to his role.

Highly versed in asset protection strategies, inspections and reports, claims settlement / management, quality assurance and General Contractor project coordination and management. Seth can identify inherent obstacles to various processes, and create actionable solutions that deliver desirable outcomes / results.
Seth attended the University of Cincinnati, interned with iStorm for 3 years and is now a full time member of the Team. Seth is also an avid golfer and takes great pride in out-hitting his Dad.

Director of Risk Management

Ethan Deddens

problem solver, critical thinker, results driven

Ethan began with iStorm interning during the summers while attending college in May 2017.

As a Quality Assurance Specialist he was responsible for overseeing roofing and siding projects that were underway. He ensured that each project was completed in a timely, professional manner, and communicated effectively and efficiently with property managers, general contractors, and public adjusters.

In Ethan’s present role he orchestrates and leads critical Risk Management functions, including policy analysis, interpretation, and underwriting guidance, providing 3rd party broker placement options for our esteemed clients. Ethan’s responsibilities extend to overseeing and managing the comprehensive insurance review and recommendation initiative for all ISG owner clients, ensuring a strategic and client-centric approach.

Ethan has a Bachelor’s degree in economics from Miami University, Oxford Ohio. Ethan enjoys golf, traveling, and attending professional sports events.

Our Partners


rather a corner stone of why+how we do business.