Mark Diehl Sullivan

Mark Diehl Sullivan

4.9
Rating: 7.0

Licensed for 27 years

Litigation Lawyer at Wilson, WY
Practice Areas: Litigation, Environmental and Natural Resources, Workers Compensation ... +4 more

5237 HHR Ranch Road, Wilson, WY

About Mark

Fees and Rates

Cost

Hourly Rates

$ 150-250 per hour

Contingency

25%-40%

Retainer

Sometimes


Payment Methods

  • Cash
  • Check

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Licenses

Licensed in Wyoming for 20 years

State: Wyoming

Acquired: 2005

Active

No misconduct found

Licensed in New York for 27 years

State: New York

Acquired: 1998

Delinquent

No misconduct found

Location

Mark D. Sullivan, P.C.

5237 HHR Ranch Road, Wilson, WY, 83014-9210

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Mark Diehl Sullivan's Reviews

Avvo Review Score

4.9 /5.0

30 Client Reviews

Showing 1 - 5 of 10 reviews | General Knowledge

Posted by Caroline | May 18, 2022 | Hired Attorney | Landlord & Tenant

Exceptional

Last year, we found ourselves in a very unfortunate dispute over language in a lease we signed with a property manager and tenants. The conflict brought me to my knees...it was one of the hardest things I have ever experienced (and I have known real pain). And we could not find an attorney to help us.... When we called Mark Sullivan and explained the situation he agreed to help us. Over the next few months he provided exceptional counsel, and we ultimately prevailed. He was always available to us, and knew exactly when to push the other side, and when to give them time. Mark's professionalism, knowledge, wisdom and expertise helped us tremendously, and I am forever grateful.

Posted by Trip | December 06, 2016 | Hired Attorney | Workers Compensation

Wyoming Workers Compensation Excellence

Mark Sullivan helped me navigate the Worker's Compensation process from start to finish. He helped explain the process making it easier to understand. He is responsive and efficient. Mark remained my advocate compassionately explaining to me different choices through a lengthy process. He was patient... and diligent despite my difficulties with memory, spinal surgeries and extenuating circumstances. Ultimately, we prevailed. I cannot speak more highly of his character, legal proficiency and tenacity.

Posted by Lisa | October 28, 2015 | Hired Attorney | Lawsuits & Disputes

Mark Sullivan has my highest recommendation, without reservation.

Mark is an excellent attorney: professional, intelligent, thorough and perceptive. He managed our case with a clear game plan, his writing was, without exception, prompt and impeccable, with close attention to detail. Mark was always knowledgable and prepared, clearly outlining issues and options at... every turn. His calm demeanor inspired great confidence throughout the legal process. Mark is so easy to work with that I plan to contact him for any legal matters that arise in the future. A smart, straight shooter and a good man.... I can recommend Mark without any hesitation whatsoever.

Posted by Kimball | October 20, 2015 | Hired Attorney | Workers Compensation

SUPERB LEGAL REPRESENTATION

Mark Sullivan is a first class lawyer. I highly recommend him! Mark successfully represented me in a Workers Compensation action, displaying dogged determination, keen anaylitic skills, a thoroughly researched knowledge of the law and confident courtroom demeaner.

Posted by Lonnie | November 13, 2014 | Workers Compensation

Honorable

Mark did a very good job of educating me in the process. He was instrumental in getting what I needed from Wyoming Worker's Compensation. He was very knowledgeable and provided fantastic arguments. He contacted me when said he would and conducted himself as nothing but professional. I think his pati...ence with me was more than exceptional. I questioned everything and he knew the answer or would find it for me. I would and have recommended his services to others.

See All Client Reviews

Mark Diehl Sullivan's Lawyer Endorsements

Endorse Mark
Stephen C Biggs headshot
Stephen Biggs

Litigation lawyer | Apr 29

Relationship: Worked together on matter

"Mark is an excellent lawyer and a very amiable person. Our firm worked with him as co-counsel on two cases in Wyoming. Mark has a solid knowledge of the law, is a skilled litigator, is deeply concerned for the well-being of his clients, and is a consummate professional. I would recommend him to others looking for a lawyer to represent them in Wyoming."

Jessica Rutzick headshot
Jessica Rutzick

Litigation lawyer | Feb 15

Relationship: Fellow lawyer in community

"Mark gets terrific results for his clients and is a really good person to boot."

Jeffrey Michael Norton headshot
Jeffrey Norton

General practice lawyer | Nov 04

Relationship: Friend

"I have known Mark for over 16 years and I can say unequivocally that he is one of the most naturally gifted lawyers I have ever known. His ability to craft legal arguments and understand complex legal issues is remarkable and make him a formidable adversary in and out of court. He is also a consummate professional and widely respected. Although these qualities alone would make him a good lawyer, Mark also is a committed and passionate advocate for his clients and a genuinely decent guy to boot. Accordingly, I recommend and endorse Mark without reservation."

View All Endorsements
Stephen C Biggs headshot
Stephen Biggs

Litigation lawyer

Richard R. Thomas headshot
Richard Thomas

Litigation lawyer

Jeffrey Michael Norton headshot
Jeffrey Norton

Litigation lawyer

Stephen Lawrence Kass headshot
Stephen Kass

Environmental and natural resources lawyer

Jessica Rutzick headshot
Jessica Rutzick

Litigation lawyer

David F. Defazio headshot
David Defazio

Litigation lawyer

Experience

Rating:  7.0 (Very Good)

Work Experience

2006 - Present

Partner, Mark D. Sullivan P.C.

1999 - 2006

Associate, Carter Ledyard & Milburn, LLP

1997 - 1999

Senior Watershed Attorney, Riverkeeper, Inc.

Associations

2010 - Present

Wyoming Trial Lawyers Association

2006 - Present

Teton County Bar Association

Sample of Legal Cases

Shaw Construction v. Rocky Mountain Hardware, 275 P.3d 1238 (2012)

Victory

Meyer v. Hatto, 198 P.3d 552 (2008)

Victory

RISD v. RIOC, 291 A.D. 2d 40; 735 N.Y.S.2d 83 (A.D. 1st Dept 2001)

Victory

See More Legal Cases

Education

1999

Pace University School of Law

LL.M - Master of Laws

1997

Pace University School of Law

J.D.

1993

Kenyon College

BA - Bachelor of Arts

Publications

2006

New York State Bar Association Journal (cover story) The EPA's New Clean Air Rules

Activity

Avvo Rating

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  • Experience & background Years licensed, work experience, education
  • Legal community recognition Peer endorsements, associations, awards
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Avvo Rating Levels
10.0 - 9.0 Superb8.9 - 8.0 Excellent7.9 - 7.0 Very Good6.9 - 6.0 Good5.9 - 5.0 Average4.9 - 4.0 Concern3.9 - 3.0 Caution2.9 - 2.0 Strong Caution1.9 - 1.0 Extreme Caution