Mark Diehl Sullivan

Mark Diehl Sullivan

4.9
Rating: 7.0

Licensed for 28 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 21 years

State: Wyoming

Acquired: 2005

Active

No misconduct found

Licensed in New York for 28 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

31 Client Reviews

Showing 6 - 10 of 10 reviews | General Knowledge

Posted by Carole | November 09, 2014 | Business

Mark Sullivan tackles the most frustrating legal issues with skill and integrity.

Our organization hired Mark Sullivan four years ago. We needed legal advice on some longstanding and ongoing issues. We were impressed with how quickly he grasped the facts and provided options. Mark did not try to rush us to litigate but rather encouraged a non court solution. Once it was clear tha...t was not to happen, he advised us on other paths. Mark was clear about the issues, estimated the costs, length of time the effort might take and guided us with dignity and expertise through the processes. We prevailed in each case. Having Mark as our attorney gives us great peace of mind.

Posted by Thomas | November 06, 2014 | Intellectual Property

Clever, Cunning, Efficient, and Excellent Communication

I can't be specific, but I hired Mark Sullivan at least three times in 5 years to help in an ongoing intellectual property dispute, which thanks to Mark is no longer "ongoing." Its over! With carefully calculated negotiations and round table toughness, Mark successfully took on a team of opposing law...yers and won for me a favorable settlement. Later he showed thorough knowledge of the law and keen resourcefulness, not only quelling opposition attacks, but also winning for me a greater reward than either of us expected. If you are looking for an attorney who knows the law, knows how to use it, and can work effectively and efficiently on your behalf, I would highly recommend Mark Sullivan.

Posted by Scot & Gary | March 26, 2013 | Business

We are SOO grateful to Mark, and would highly recommend him to anyone.

We have hired Mark on 3 separate occasions; twice to review minor issues for us, and once for an extremely large problem that was potentially devastating. We last hired Mark to help us (and another great attorney, Richard R. Thomas, of Scottsdale, AZ) with a complex commercial litigation case involv...ing a $Trillion multinational corporation with unlimited legal/financial resources. We have known other lawyers with big egos and control issues. Not Mark. He is great to work with! Mark collaborated with our other attorney extremely well. Additionally, he welcomed our input as clients, and worked closely with us every step of the way. This was a particularly complex and challenging case that required attorneys to do detective work and extensive research. Whatever Mark didn't already know, he learned or figured out; he didn't just stick with strategies he was familiar with or had previously employed. Mark was impressively thorough! Further, his preparation for hearings, depositions, etc. was not only noteworthy, but admirable. Mark's high levels of professionalism, ethics, and true integrity served us well; and, we believe, added even more credibility to our case in the eyes of the judges. It is our opinion that any judge, jury, arbitrator, or mediator will not only like Mark, but, most importantly, really respect him. Mark's billing practices have been very fair, and he has deserved every penny. Mark has heard our "thank you's", witnessed our tears of joy, and has felt our genuine hugs... and there is still gratitude we have yet to express for what he has done for us. While we are hoping to never again be involved in any type of lawsuit, we would, without hesitation, put our trust in Mark D. Sullivan again.

Posted by Pauline | February 25, 2013 | Contracts & Agreements

Recommended wholeheartedly & without reservation

The case Mark handled for me and my husband was a breach of contract, fraud and racketeering case involving multiple plaintiffs against a modular homebuilder that had closed up shop, leaving us all with partially-completed but fully-paid-for homes. Mark's representation of us included a hearing in C...heyenne in which we were seeking a preliminary injunction freezing the defendants' assets which were in danger of being liquidated. Ultimately, thanks to Mark's expert advice, we elected to have him guide our case through mediation, and we successfully avoided going to court. Without Mark's tireless efforts, his impeccable professionalism, and--perhaps most importantly--his vision in bringing racketeering charges to bear in the case, our outcome would likely have been very different. We remain profoundly grateful for Mark's comprehensive evaluation of our complaint, his faith in the strength of our case, and the herculean effort he exerted on our behalf. We recommend him wholeheartedly and without reservation.

Posted by Diane | February 21, 2013 | Business

An Attorney who cares

As a member of a team to find a new Attorney to represent our Not for Profit organization, I was pleased to bring Mark Sullivan's name to the table. We did engage Mark's services and for the past 6 years he has proven his value over and over. His diverse knowledge and expertise continues to provide ...us with superior guidance through the complex process of negotiating with Lenders, Title companies, member disputes and contracts. It is Mark's "tough but kind" demeanor that has kept a calm perspective in even the most uncomfortable and challenging situations. His timely responsiveness, absolutely fair billing, and integrity have confirmed our decision in choosing Mark for all of our legal needs and has inspired us to unequivocally recommend him to members of the general public.

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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