Michael Mosberg is an accomplished American attorney recognized for his work in family law, matrimonial litigation, and high-net-worth divorce cases. As a founding partner of Mosberg Sharma Stambleck Gross LLP (MSSG), he has developed a career handling complex financial disputes, child custody matters, and sophisticated marital agreements in New York and Connecticut.
His professional influence goes beyond representing clients. From leading the American Bar Association’s Family Law Section to publishing legal scholarship and helping resolve matrimonial disputes through mediation, Mosberg has established a substantial presence in the American legal profession.
His credentials have also attracted independent recognition. In 2026, Chambers and Partners ranked him in its High Net Worth guide, while Best Lawyers named him 2026 Lawyer of the Year for Family Law in New York City.
This article examines his background, education, professional development, legal specialties, leadership roles, published work, and achievements, using information from his law firm, professional associations, legal directories, and court resources.
Who Is Michael Mosberg?
Michael Mosberg is a New York-based matrimonial and family law attorney who represents individuals navigating difficult legal issues involving marriage, separation, divorce, and parental responsibilities. His professional name is Michael A. Mosberg, and he is a founding partner of the Manhattan-based law firm Mosberg Sharma Stambleck Gross LLP.
His practice focuses particularly on high-net-worth individuals, including business owners, entrepreneurs, corporate executives, and their spouses. These matters often involve substantial assets, complicated ownership arrangements, and financial questions that require coordination between lawyers and other specialists.
Unlike attorneys who concentrate exclusively on courtroom disputes, he also works toward negotiated settlements and private resolutions. His firm’s biography describes a practice that combines financial analysis, dispute resolution, litigation, and cooperation with professionals in related fields.
Michael Mosberg at a Glance
| Category | Verified information |
|---|---|
| Full professional name | Michael A. Mosberg |
| Profession | Attorney and certified matrimonial mediator |
| Primary specialization | Family and matrimonial law |
| Current position | Founding Partner, Mosberg Sharma Stambleck Gross LLP |
| Location | New York City, United States |
| Undergraduate education | University of Michigan |
| Law degree | Brooklyn Law School |
| New York bar admission | 1998 |
| Connecticut bar admission | 2014 |
| Notable leadership | Former Chair, ABA Family Law Section |
| Recognition | Chambers High Net Worth, Best Lawyers, Super Lawyers |
| Current firm established | 2022 |
Information cross-checked against professional biographies, the American Academy of Matrimonial Lawyers, and independent legal directories.
Michael Mosberg’s Early Life and Educational Background
A successful legal career rarely develops overnight. It typically requires years of academic training, courtroom experience, professional relationships, and continuous study of changing laws.
For Michael Mosberg, that foundation included undergraduate studies in psychology, formal legal education, and experience within the federal judicial system.
Undergraduate Studies at the University of Michigan
Mosberg graduated from the University of Michigan in 1994 with a Bachelor of Arts in Psychology, earning his degree with distinction.
Psychology is relevant to family law because matrimonial disputes involve more than legal documents or financial calculations. Attorneys regularly work with individuals experiencing emotional stress, communication difficulties, parenting disagreements, and major changes in family relationships.
A background in psychology does not automatically establish expertise in counseling or behavioral science. It can, however, provide useful academic context for understanding interpersonal conflict and the human dimensions of legal disputes.
Legal Education at Brooklyn Law School
He subsequently attended Brooklyn Law School, earning his Juris Doctor in 1997. His educational credentials include recognition as a Richardson Scholar and participation in the Moot Court Honor Society.
Moot court provides law students with opportunities to research legal questions, prepare arguments, analyze judicial decisions, and practice presenting cases.
These skills are particularly relevant to matrimonial litigation, where attorneys must explain complicated financial or family circumstances while advocating for their clients’ legal positions.
Early Judicial Experience
Before entering private practice, Mosberg served as a law clerk to the Honorable Virginia M. Morgan of the United States District Court for the Eastern District of Michigan.
Judicial clerkships expose young lawyers to court procedures, legal research, judicial reasoning, and the preparation of legal decisions. They also provide practical insight into how courts examine evidence and evaluate arguments.
This experience formed part of Mosberg’s professional development before he concentrated on private matrimonial practice.
His New York bar admission followed in 1998, and he was admitted to practice in Connecticut in 2014.
Michael Mosberg’s Legal Career and Professional Growth
The professional journey of Michael Mosberg reflects a sustained commitment to matrimonial and family law rather than frequent changes between unrelated legal specialties.
Before establishing his current firm, he practiced at Aronson Mayefsky & Sloan LLP, a New York matrimonial law firm. Historical professional profiles and his earlier legal publications document that association.
His career also included participation in professional committees, continuing legal education programs, and organizations dedicated to improving family law practice.
Over time, these activities helped establish his professional profile beyond his individual legal cases.
Founding Mosberg Sharma Stambleck Gross LLP
One of the most significant milestones in his career occurred in 2022.
That year, Mosberg and fellow matrimonial attorneys established Mosberg Sharma Stambleck Gross LLP (MSSG), a boutique family and matrimonial law practice based in New York City.
According to the firm’s history, its founders had already worked together for approximately two decades before establishing the practice.
The founding team includes Michael A. Mosberg, Sherri Sharma, Peter Stambleck, and Jillian Gross. The firm emphasizes collaborative representation, confidential client service, and coordinated legal strategies for complex matrimonial matters.
What Makes a Boutique Matrimonial Law Firm Different?
A boutique law firm concentrates its services within a particular legal field instead of offering a broad range of unrelated legal services.
For MSSG, that concentration is family and matrimonial law. Its work encompasses divorce, asset division, custody, support, and marital agreements.
Specialization may be especially valuable where a case involves multiple overlapping concerns. A business valuation dispute, for example, may also affect property division, support calculations, tax planning, and settlement negotiations.
A focused practice does not guarantee a particular result. The important question is whether the firm’s relevant experience matches the client’s specific circumstances.
What Areas of Family Law Does Michael Mosberg Specialize In?
The work of Michael Mosberg covers several interconnected areas of matrimonial law, with particular emphasis on cases involving substantial wealth and complicated financial arrangements.
Understanding these practice areas helps explain why his professional background attracts attention from individuals seeking sophisticated legal representation.
1. High-Net-Worth Divorce and Financial Settlements
High-net-worth divorce is a major component of Mosberg’s practice.
These cases may involve privately held companies, investment portfolios, real estate, retirement accounts, executive compensation, valuable personal property, and ownership interests that are difficult to evaluate.
A central challenge is identifying what assets exist, determining their appropriate valuations, and establishing how they should be treated under applicable matrimonial law.
In New York, equitable distribution does not necessarily mean a 50/50 division. Courts consider legally relevant circumstances when determining a fair distribution of marital property.
For a high-value case, even a relatively small valuation difference may have substantial financial consequences.
That is why complex matrimonial representation can require collaboration with forensic accountants, valuation experts, estate-planning professionals, and financial advisers.
2. Prenuptial and Postnuptial Agreements
Another important area of Michael Mosberg’s practice involves agreements that establish financial arrangements between spouses.
A prenuptial agreement is entered into before marriage, while a postnuptial agreement is created after a couple is already married.
Such agreements may address property ownership, asset distribution, financial responsibilities, and certain rights if the marriage ends.
Mosberg has written extensively about postnuptial agreements, including a scholarly article co-authored with Patricia Kindregan titled Ten Practice Tips for Postnuptial Agreements: Drafting Considerations and Formalities.
The article appeared in the American Bar Association’s Family Law Quarterly, Volume 52, Number 2, in 2018.
His work on these agreements reflects attention to drafting requirements and enforceability issues, not simply the negotiation of financial terms.
3. Child Custody and Parenting Arrangements
Financial concerns are only one part of divorce proceedings. When children are involved, questions about parenting schedules, decision-making authority, and family stability can become equally significant.
Mosberg’s matrimonial practice includes child custody and related disputes.
Under New York law, courts distinguish between legal custody, which concerns major decisions affecting a child, and physical custody, which concerns the child’s day-to-day living arrangements.
Judges make custody decisions according to the child’s best interests, including health, safety, caregiving history, and other relevant factors.
For families, an effective legal strategy must therefore address practical parenting arrangements as well as the applicable legal standards.
4. Spousal Support and Child Support
Spousal maintenance and child support require careful examination of income, financial obligations, and the circumstances of the parties.
In high-net-worth matters, calculating income can be especially complicated when compensation includes bonuses, business distributions, deferred payments, or irregular earnings.
New York applies statutory rules to child support and maintenance, but the analysis can become more complex when financial circumstances fall outside straightforward employment arrangements.
Michael Mosberg has participated in professional discussions about support issues, including public commentary on the experiences of men seeking alimony.
His commentary on that subject illustrates how financial roles within marriage and expectations surrounding spousal support can become important parts of the legal conversation.
Michael Mosberg’s Approach to Mediation and Litigation
A notable aspect of Michael Mosberg’s professional profile is his involvement in both contested litigation and alternative dispute resolution.
Not every divorce requires a lengthy courtroom battle. Parties may resolve their differences through negotiations, mediation, or other settlement processes, depending on the case.
Mosberg is listed by the American Academy of Matrimonial Lawyers as an AAML Certified Mediator. His firm’s current biography also identifies him as someone retained for mediation, expert work, and special-master assignments in complex matrimonial matters.
How Divorce Mediation Works
Mediation involves a neutral third party who assists individuals in discussing disputes and exploring potential agreements.
Unlike a judge, a mediator generally does not impose a binding decision on the parties. The process is intended to support voluntary problem-solving.
New York’s Unified Court System explains that mediation can be useful for disputes involving property, debt, financial support, and parenting arrangements.
It also warns that mediation may be inappropriate in cases involving domestic violence, abuse, or circumstances that prevent safe and balanced participation.
Why Litigation Experience Still Matters
Settlement is not always possible.
When spouses disagree about business ownership, financial disclosures, custody arrangements, or the interpretation of legal agreements, judicial intervention may become necessary.
An attorney experienced in both negotiation and litigation can evaluate potential compromises while preparing to pursue disputed issues in court.
Mosberg’s stated approach reflects this combination: seeking private resolutions where appropriate while maintaining the ability to litigate financial and custody matters.
Professional Leadership and American Bar Association Involvement
Leadership within professional legal organizations represents another major part of Michael Mosberg’s career.
He served as Chair of the American Bar Association’s Family Law Section during the 2020–2021 leadership term.
His assumption of that leadership role is documented in the firm’s announcement dated August 1, 2020, as well as in American Bar Association publications carrying his contributions as section chair.
The ABA Family Law Section brings together professionals involved in family-related legal practice, legal education, and the development of legal scholarship.
Serving as chair entails professional leadership responsibilities beyond the ordinary work of representing clients.
Contributions to Legal Education
Mosberg has also delivered presentations to legal organizations, including the American Bar Association, New York State Bar Association, New York City Bar Association, and American Academy of Matrimonial Lawyers.
His lecture topics have included matrimonial litigation, financial disclosure, deposition techniques, marital agreements, and child support.
He has also been involved in professional committees concerning matrimonial practice and court procedures.
This continued engagement with legal education is a meaningful distinction because it demonstrates involvement in discussions about how family law is taught, practiced, and administered.
Michael Mosberg’s Awards and Professional Recognition in 2026
Michael Mosberg has earned recognition from several established legal ranking organizations.
These distinctions provide independent evidence of professional visibility, although they should not be treated as guarantees of successful results in individual cases.
Chambers and Partners High Net Worth 2026
In its 2026 High Net Worth guide, Chambers and Partners ranked Mosberg in Band 2 for Family/Matrimonial: High Net Worth in New York.
His Chambers profile indicates five years of ranking history in that practice area.
Chambers also includes professional feedback describing his attention to detail and practical working style. These statements represent the views reported by the ranking organization rather than independently proven outcomes for particular clients.
Best Lawyers Recognition
Best Lawyers has recognized him in Family Law since 2014.
Its current professional listing names him 2026 Lawyer of the Year in Family Law for New York City and includes him in the 2027 edition of The Best Lawyers in America.
The Lawyer of the Year designation is associated with a particular practice area and geographic market, so it should not be interpreted as a claim that an individual is the single best lawyer nationwide.
Super Lawyers and Other Honors
Super Lawyers lists Mosberg among its New York Family Law selections from 2013 through 2026, following earlier Rising Stars selections in 2011 and 2012.
His professional materials also document recognition in the 2024 Lawdragon 500 Leading Family Lawyers in the United States.
He received American Bar Association Family Law Section Chair’s Cup recognition for contributions during the 2013–2014 and 2019–2020 periods.
Together, these records show recognition across multiple stages of his professional career.
Publications, Legal Writing, and Thought Leadership
The published work of Michael Mosberg provides an additional way to understand his professional interests.
Rather than relying solely on biographical descriptions, readers can examine the subjects he has addressed in legal articles, commentary, and professional presentations.
His writing covers matrimonial agreements, courtroom procedures, asset disputes, and developments affecting family law practitioners.
Research on Postnuptial Agreements
His co-authored publication on postnuptial agreements examines legal drafting considerations and formal requirements.
The topic is particularly relevant to marriages involving significant assets, inheritance considerations, or changing financial circumstances.
Clear documentation, informed legal advice, and compliance with applicable formalities are important when creating agreements intended to affect future property rights.
Mosberg’s scholarly contribution offers evidence of sustained engagement with this specialized area of matrimonial practice.
The Intersection of Fine Art and Divorce
One particularly interesting publication is The Intersection of Fine Art and Divorce, co-authored with Heidi Harris and published in 2017.
The article examines complications surrounding art collections when married couples separate.
Artwork can generate difficult disputes because payment records, ownership documentation, purchase history, gifts, and appreciation in value may all become relevant.
A valuable painting is not necessarily treated as belonging exclusively to the spouse who paid for it. The broader circumstances and governing law matter.
This subject provides a useful illustration of the financial sophistication often required in high-value matrimonial cases.
Courtroom Practice and Evidence
Mosberg has also written and lectured about deposition techniques, witness preparation, electronic evidence, and trial practice.
A deposition is a formal process for obtaining sworn testimony before trial and may play an important role in contested litigation.
His professional profiles identify work concerning deposition pitfalls and the use of witness consultants in client preparation.
These subjects demonstrate attention to the practical skills required to investigate disputed facts and present evidence effectively.
What Distinguishes Michael Mosberg’s Professional Practice?
Several characteristics emerge when Michael Mosberg’s independently documented credentials are considered together.
The most significant is the intersection of three areas: complex financial litigation, professional leadership, and alternative dispute resolution.
His practice is particularly relevant to cases where legal questions cannot be separated easily from business, tax, personal, or family considerations.
Another distinctive element is his involvement with professionals beyond the legal field. His firm’s current biography describes collaboration with financial, estate-planning, public-relations, and other specialists when particular matters require their expertise.
That cross-disciplinary model may help address issues that would otherwise be considered in isolation, such as the impact of dividing an ownership interest on future income or estate planning.
His mediation work offers a different dimension. It suggests professional experience examining disputes not only through the perspective of advocacy but also through structured efforts to reach agreements.
These characteristics are supported by his published practice description and credentials. They do not establish a particular win rate, client satisfaction level, or superiority over other attorneys, none of which can be determined from the cited information alone.
How to Evaluate Michael Mosberg for Legal Representation
Selecting a family lawyer is a consequential decision, especially when a case involves substantial property or children’s welfare.
Readers considering Michael Mosberg or another experienced matrimonial attorney should move beyond awards and evaluate the practical fit between the lawyer and their circumstances.
A useful initial consultation should address the following questions:
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Relevant experience: Has the attorney handled matters involving assets, family arrangements, or disputes similar to yours?
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Case strategy: Which issues appear suitable for negotiation, mediation, or litigation?
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Financial expertise: Will forensic accountants, valuation professionals, or tax specialists be necessary?
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Communication: Who will handle routine correspondence, and how will important decisions be communicated?
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Fees: What retainer, billing structure, additional professional costs, and possible litigation expenses should be anticipated?
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Risk assessment: What are the principal uncertainties, potential complications, and realistic legal options?
A strong attorney-client relationship depends on more than a recognizable name.
Clear communication, realistic expectations, transparent fees, and a strategy tailored to the facts are essential considerations.
Preparing for a Matrimonial Law Consultation
Before meeting with counsel, organize the documents most relevant to the dispute.
For financial matters, these may include tax returns, bank statements, business ownership documents, investment records, property information, and existing marital agreements.
For parenting disputes, relevant materials may include school schedules, current caregiving arrangements, communications concerning parenting, and documents relating to existing orders.
New York Courts provides current matrimonial forms and resources, including updated financial disclosure and contested-divorce materials effective during 2025 and 2026. These resources can help prospective clients understand the documentation a divorce proceeding may require.
Sensitive records should be shared securely and in accordance with a lawyer’s instructions.
Michael Mosberg’s Law Firm and Professional Contact Information
For individuals looking for verified professional information, the most reliable starting point is the firm’s current website rather than an outdated directory listing.
Matrimonial and Family Law — New York City
1270 Avenue of the Americas, Suite 2110, New York, NY 10020
Telephone: 212-678-8500
Email: mosberg@mssglaw.com
The firm’s official biography and the American Academy of Matrimonial Lawyers directory provide the most directly relevant professional contact details. Because third-party directories sometimes retain older suite numbers or biographical information, contact details should be confirmed before visiting.
Frequently Asked Questions About Michael Mosberg
1. Who is Michael Mosberg, and why is he well known?
Michael Mosberg is an American family law attorney and founding partner of Mosberg Sharma Stambleck Gross LLP in New York City. He is known professionally for handling complex matrimonial disputes, particularly high-net-worth divorce matters involving financial assets, support, custody, and marital agreements.
He has also served as Chair of the American Bar Association’s Family Law Section and has received recognition from Chambers, Best Lawyers, and Super Lawyers. His legal writing, educational presentations, and mediation credentials contribute to his professional reputation.
2. Where did Michael Mosberg study law?
Mosberg earned a Bachelor of Arts in Psychology with distinction from the University of Michigan in 1994.
He subsequently received his Juris Doctor from Brooklyn Law School in 1997, where his academic credentials included Richardson Scholar recognition and membership in the Moot Court Honor Society. Before entering private practice, he served as a federal judicial law clerk in Michigan.
3. What kind of cases does Michael Mosberg handle?
Michael Mosberg focuses on matrimonial and family law, particularly complex divorce proceedings, financial disputes, marital agreements, child custody matters, and support questions.
His firm’s practice also involves substantial asset valuations and business interests. In addition to representing clients in disputed matters, he works as a certified mediator and may be retained for expert or special-master assignments in complex matrimonial proceedings.
4. Is Michael Mosberg recognized as a leading divorce attorney?
He has received several documented professional distinctions, including a Band 2 ranking in Chambers High Net Worth 2026 for New York Family/Matrimonial law.
Best Lawyers also named him Lawyer of the Year for Family Law in New York City in 2026, and Super Lawyers lists him among its selected New York Family Law attorneys for 2026.
These recognitions support his established professional standing, although prospective clients should still independently assess relevant experience, fees, availability, and suitability for their case.
5. How can someone contact Michael Mosberg or arrange a consultation?
Interested individuals can contact his firm, Mosberg Sharma Stambleck Gross LLP, through its official website, telephone number, or published professional email address.
The firm’s listed New York telephone number is 212-678-8500, and its official website is mssglaw.com.
Before an initial consultation, prospective clients should prepare a brief description of their legal circumstances, identify any immediate deadlines, and gather relevant financial or family documents. They should also confirm whether the firm can accept the matter and what consultation fees or conflicts procedures apply.
Conclusion: Understanding Michael Mosberg’s Career and Legal Influence
The career of Michael Mosberg demonstrates how specialized legal practice, sustained professional involvement, and subject-matter scholarship can contribute to recognition within the family law profession.
His experience encompasses high-net-worth matrimonial disputes, complicated financial questions, marital agreements, custody proceedings, and alternative dispute resolution. His former leadership of the American Bar Association’s Family Law Section and continuing recognition in major legal rankings provide additional evidence of his professional standing.
His publications are especially useful for readers who want to understand the substantive issues behind his legal practice, including postnuptial agreements, evidence gathering, and the division of valuable assets.
For anyone researching his qualifications or considering legal representation, the next step is straightforward: review his official firm biography, verify his current professional credentials, and arrange a consultation to discuss the facts and requirements of the particular legal matter. Awards can inform that decision, but relevant expertise, professional judgment, and client-lawyer compatibility should ultimately guide it.
